diff --git a/changelog_unreleased/javascript/pr-7709.md b/changelog_unreleased/javascript/pr-7709.md
new file mode 100644
index 000000000..9ffff8eec
--- /dev/null
+++ b/changelog_unreleased/javascript/pr-7709.md
@@ -0,0 +1,14 @@
+#### Keep comments position for assignments/variables ([#7709](https://github.com/prettier/prettier/pull/7709) by [@sosukesuzuki](https://github.com/sosukesuzuki))
+
+<!-- prettier-ignore -->
+```jsx
+// Input
+const foo = /* comments */
+  bar;
+
+// Prettier stable
+const foo /* comments */ = bar;
+
+// Prettier master
+const foo = /* comments */ bar;
+```
diff --git a/src/language-js/comments.js b/src/language-js/comments.js
index e619d04af..31fb59fd3 100644
--- a/src/language-js/comments.js
+++ b/src/language-js/comments.js
@@ -818,7 +818,8 @@ function handleVariableDeclaratorComments(
     (followingNode.type === "ObjectExpression" ||
       followingNode.type === "ArrayExpression" ||
       followingNode.type === "TemplateLiteral" ||
-      followingNode.type === "TaggedTemplateExpression")
+      followingNode.type === "TaggedTemplateExpression" ||
+      isBlockComment(comment))
   ) {
     addLeadingComment(followingNode, comment);
     return true;
diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index 87a825c03..8ee3608f1 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -5750,7 +5750,7 @@ function printBinaryishExpressions(
 
 function printAssignmentRight(leftNode, rightNode, printedRight, options) {
   if (hasLeadingOwnLineComment(options.originalText, rightNode, options)) {
-    return indent(concat([hardline, printedRight]));
+    return indent(concat([line, printedRight]));
   }
 
   const canBreak =
diff --git a/src/main/comments.js b/src/main/comments.js
index 60fbe5a8d..1c1758d93 100644
--- a/src/main/comments.js
+++ b/src/main/comments.js
@@ -3,6 +3,7 @@
 const assert = require("assert");
 const {
   concat,
+  line,
   hardline,
   breakParent,
   indent,
@@ -387,10 +388,15 @@ function printLeadingComment(commentPath, print, options) {
   // Leading block comments should see if they need to stay on the
   // same line or not.
   if (isBlock) {
-    return concat([
-      contents,
-      hasNewline(options.originalText, options.locEnd(comment)) ? hardline : " "
-    ]);
+    const lineBreak = hasNewline(options.originalText, options.locEnd(comment))
+      ? hasNewline(options.originalText, options.locStart(comment), {
+          backwards: true
+        })
+        ? hardline
+        : line
+      : " ";
+
+    return concat([contents, lineBreak]);
   }
 
   return concat([contents, hardline]);
diff --git a/tests/assignment_comments/__snapshots__/jsfmt.spec.js.snap b/tests/assignment_comments/__snapshots__/jsfmt.spec.js.snap
index c30a57fd0..08130fb90 100644
--- a/tests/assignment_comments/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/assignment_comments/__snapshots__/jsfmt.spec.js.snap
@@ -1,6 +1,253 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`assignment_comments.js 1`] = `
+exports[`function.js 1`] = `
+====================================options=====================================
+parsers: ["flow", "typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+f1 = (
+  a =
+  //comment
+  b
+) => {};
+  
+f2 = (
+  a = //comment
+  b
+) => {};
+  
+f3 = (
+  a =
+  b //comment
+) => {};
+  
+f4 = // Comment
+  () => {};
+
+f5 =
+  
+  // Comment
+  
+ () => {}
+  
+f6 = /* comment */
+  
+  // Comment
+  
+  () => {}
+  
+let f1 = (
+  a =
+  //comment
+  b
+) => {};
+  
+let f2 = (
+  a = //comment
+  b
+) => {};
+  
+let f3 = (
+  a =
+  b //comment
+) => {};
+  
+let f4 = // Comment
+  () => {};
+  
+let f5 =
+  
+  // Comment
+  
+  () => {}
+  
+let f6 = /* comment */
+  
+  // Comment
+  
+  () => {}
+
+=====================================output=====================================
+f1 = (
+  //comment
+  a = b
+) => {};
+
+f2 = (
+  a = b //comment
+) => {};
+
+f3 = (
+  a = b //comment
+) => {};
+
+f4 = () => {}; // Comment
+
+f5 =
+  // Comment
+
+  () => {};
+
+f6 =
+  /* comment */
+
+  // Comment
+
+  () => {};
+
+let f1 = (
+  //comment
+  a = b
+) => {};
+
+let f2 = (
+  a = b //comment
+) => {};
+
+let f3 = (
+  a = b //comment
+) => {};
+
+let f4 = () => {}; // Comment
+
+let f5 =
+  // Comment
+
+  () => {};
+
+let f6 =
+  /* comment */
+
+  // Comment
+
+  () => {};
+
+================================================================================
+`;
+
+exports[`identifier.js 1`] = `
+====================================options=====================================
+parsers: ["flow", "typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+const kochabCooieGameOnOboleUnweave = // ???
+      annularCooeedSplicesWalksWayWay;
+
+const bifornCringerMoshedPerplexSawder = // !!!
+  glimseGlyphsHazardNoopsTieTie +
+  averredBathersBoxroomBuggyNurl -
+  anodyneCondosMalateOverateRetinol;
+
+=====================================output=====================================
+const kochabCooieGameOnOboleUnweave = annularCooeedSplicesWalksWayWay; // ???
+
+const bifornCringerMoshedPerplexSawder = // !!!
+  glimseGlyphsHazardNoopsTieTie +
+  averredBathersBoxroomBuggyNurl -
+  anodyneCondosMalateOverateRetinol;
+
+================================================================================
+`;
+
+exports[`number.js 1`] = `
+====================================options=====================================
+parsers: ["flow", "typescript"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+fnNumber =
+  // Comment
+  3;
+
+fnNumber =
+
+  // Comment
+
+  3;
+
+fnNumber =
+  // Comment0
+  // Comment1
+  3;
+
+fnNumber = /* comment */
+  3;
+
+fnNumber = /* comments0 */
+  /* comments1 */
+  3;
+
+fnNumber =
+  // Comment
+  3;
+
+var fnNumber =
+
+  // Comment
+
+  3;
+
+var fnNumber =
+  // Comment0
+  // Comment1
+  3;
+
+var fnNumber = /* comment */
+  3;
+
+var fnNumber = /* comments0 */
+  /* comments1 */
+  3;
+
+=====================================output=====================================
+fnNumber =
+  // Comment
+  3;
+
+fnNumber =
+  // Comment
+
+  3;
+
+fnNumber =
+  // Comment0
+  // Comment1
+  3;
+
+fnNumber = /* comment */ 3;
+
+fnNumber =
+  /* comments0 */
+  /* comments1 */
+  3;
+
+fnNumber =
+  // Comment
+  3;
+
+var fnNumber =
+  // Comment
+
+  3;
+
+var fnNumber =
+  // Comment0
+  // Comment1
+  3;
+
+var fnNumber = /* comment */ 3;
+
+var fnNumber =
+  /* comments0 */
+  /* comments1 */
+  3;
+
+================================================================================
+`;
+
+exports[`string.js 1`] = `
 ====================================options=====================================
 parsers: ["flow", "typescript"]
 printWidth: 80
@@ -10,7 +257,38 @@ fnString =
   // Comment
   'some' + 'long' + 'string';
 
-var fnString =
+fnString =
+  // Comment
+
+  'some' + 'long' + 'string';
+
+fnString =
+
+  // Comment
+
+  'some' + 'long' + 'string';
+
+fnString =
+  /* comment */
+  'some' + 'long' + 'string';
+
+fnString =
+  /**
+   * multi-line
+   */
+  'some' + 'long' + 'string';
+
+fnString =
+  /* inline */ 'some' + 'long' + 'string' + 'some' + 'long' + 'string' + 'some' + 'long' + 'string' + 'some' + 'long' + 'string';
+
+fnString = // Comment0
+  // Comment1
+  'some' + 'long' + 'string';
+
+fnString = // Comment
+  'some' + 'long' + 'string';
+
+fnString =
   // Comment
   'some' + 'long' + 'string';
 
@@ -38,35 +316,59 @@ var fnString =
 var fnString =
   /* inline */ 'some' + 'long' + 'string' + 'some' + 'long' + 'string' + 'some' + 'long' + 'string' + 'some' + 'long' + 'string';
 
-var fnString = // Comment
-  // Comment
+var fnString = // Comment0
+  // Comment1
   'some' + 'long' + 'string';
 
 var fnString = // Comment
   'some' + 'long' + 'string';
 
-let f1 = (
-  a =
-  //comment
-  b
-) => {};
-
-let f2 = (
-  a = //comment
-  b
-) => {};
-
-let f3 = (
-  a =
-  b //comment
-) => {};
-
 =====================================output=====================================
 fnString =
   // Comment
   "some" + "long" + "string";
 
-var fnString =
+fnString =
+  // Comment
+
+  "some" + "long" + "string";
+
+fnString =
+  // Comment
+
+  "some" + "long" + "string";
+
+fnString =
+  /* comment */
+  "some" + "long" + "string";
+
+fnString =
+  /**
+   * multi-line
+   */
+  "some" + "long" + "string";
+
+fnString =
+  /* inline */ "some" +
+  "long" +
+  "string" +
+  "some" +
+  "long" +
+  "string" +
+  "some" +
+  "long" +
+  "string" +
+  "some" +
+  "long" +
+  "string";
+
+fnString = // Comment0
+  // Comment1
+  "some" + "long" + "string";
+
+fnString = "some" + "long" + "string"; // Comment
+
+fnString =
   // Comment
   "some" + "long" + "string";
 
@@ -104,24 +406,11 @@ var fnString =
   "long" +
   "string";
 
-var fnString = // Comment
-  // Comment
+var fnString = // Comment0
+  // Comment1
   "some" + "long" + "string";
 
 var fnString = "some" + "long" + "string"; // Comment
 
-let f1 = (
-  //comment
-  a = b
-) => {};
-
-let f2 = (
-  a = b //comment
-) => {};
-
-let f3 = (
-  a = b //comment
-) => {};
-
 ================================================================================
 `;
diff --git a/tests/assignment_comments/function.js b/tests/assignment_comments/function.js
new file mode 100644
index 000000000..791193b7c
--- /dev/null
+++ b/tests/assignment_comments/function.js
@@ -0,0 +1,61 @@
+f1 = (
+  a =
+  //comment
+  b
+) => {};
+  
+f2 = (
+  a = //comment
+  b
+) => {};
+  
+f3 = (
+  a =
+  b //comment
+) => {};
+  
+f4 = // Comment
+  () => {};
+
+f5 =
+  
+  // Comment
+  
+ () => {}
+  
+f6 = /* comment */
+  
+  // Comment
+  
+  () => {}
+  
+let f1 = (
+  a =
+  //comment
+  b
+) => {};
+  
+let f2 = (
+  a = //comment
+  b
+) => {};
+  
+let f3 = (
+  a =
+  b //comment
+) => {};
+  
+let f4 = // Comment
+  () => {};
+  
+let f5 =
+  
+  // Comment
+  
+  () => {}
+  
+let f6 = /* comment */
+  
+  // Comment
+  
+  () => {}
diff --git a/tests/assignment_comments/identifier.js b/tests/assignment_comments/identifier.js
new file mode 100644
index 000000000..e900cea7c
--- /dev/null
+++ b/tests/assignment_comments/identifier.js
@@ -0,0 +1,7 @@
+const kochabCooieGameOnOboleUnweave = // ???
+      annularCooeedSplicesWalksWayWay;
+
+const bifornCringerMoshedPerplexSawder = // !!!
+  glimseGlyphsHazardNoopsTieTie +
+  averredBathersBoxroomBuggyNurl -
+  anodyneCondosMalateOverateRetinol;
diff --git a/tests/assignment_comments/number.js b/tests/assignment_comments/number.js
new file mode 100644
index 000000000..24ed9f43a
--- /dev/null
+++ b/tests/assignment_comments/number.js
@@ -0,0 +1,43 @@
+fnNumber =
+  // Comment
+  3;
+
+fnNumber =
+
+  // Comment
+
+  3;
+
+fnNumber =
+  // Comment0
+  // Comment1
+  3;
+
+fnNumber = /* comment */
+  3;
+
+fnNumber = /* comments0 */
+  /* comments1 */
+  3;
+
+fnNumber =
+  // Comment
+  3;
+
+var fnNumber =
+
+  // Comment
+
+  3;
+
+var fnNumber =
+  // Comment0
+  // Comment1
+  3;
+
+var fnNumber = /* comment */
+  3;
+
+var fnNumber = /* comments0 */
+  /* comments1 */
+  3;
diff --git a/tests/assignment_comments/assignment_comments.js b/tests/assignment_comments/string.js
similarity index 52%
rename from tests/assignment_comments/assignment_comments.js
rename to tests/assignment_comments/string.js
index 29ac7b4d3..489a018d0 100644
--- a/tests/assignment_comments/assignment_comments.js
+++ b/tests/assignment_comments/string.js
@@ -2,7 +2,38 @@ fnString =
   // Comment
   'some' + 'long' + 'string';
 
-var fnString =
+fnString =
+  // Comment
+
+  'some' + 'long' + 'string';
+
+fnString =
+
+  // Comment
+
+  'some' + 'long' + 'string';
+
+fnString =
+  /* comment */
+  'some' + 'long' + 'string';
+
+fnString =
+  /**
+   * multi-line
+   */
+  'some' + 'long' + 'string';
+
+fnString =
+  /* inline */ 'some' + 'long' + 'string' + 'some' + 'long' + 'string' + 'some' + 'long' + 'string' + 'some' + 'long' + 'string';
+
+fnString = // Comment0
+  // Comment1
+  'some' + 'long' + 'string';
+
+fnString = // Comment
+  'some' + 'long' + 'string';
+
+fnString =
   // Comment
   'some' + 'long' + 'string';
 
@@ -30,25 +61,9 @@ var fnString =
 var fnString =
   /* inline */ 'some' + 'long' + 'string' + 'some' + 'long' + 'string' + 'some' + 'long' + 'string' + 'some' + 'long' + 'string';
 
-var fnString = // Comment
-  // Comment
+var fnString = // Comment0
+  // Comment1
   'some' + 'long' + 'string';
 
 var fnString = // Comment
   'some' + 'long' + 'string';
-
-let f1 = (
-  a =
-  //comment
-  b
-) => {};
-
-let f2 = (
-  a = //comment
-  b
-) => {};
-
-let f3 = (
-  a =
-  b //comment
-) => {};
diff --git a/tests/comments/__snapshots__/jsfmt.spec.js.snap b/tests/comments/__snapshots__/jsfmt.spec.js.snap
index 56209f896..685f6f170 100644
--- a/tests/comments/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/comments/__snapshots__/jsfmt.spec.js.snap
@@ -929,12 +929,7 @@ import(
   /* Hello */
 );
 
-wrap(
-  import(
-    /* Hello */
-    "something"
-  )
-);
+wrap(import(/* Hello */ "something"));
 
 ================================================================================
 `;
@@ -981,12 +976,7 @@ import(
   /* Hello */
 )
 
-wrap(
-  import(
-    /* Hello */
-    "something"
-  )
-)
+wrap(import(/* Hello */ "something"))
 
 ================================================================================
 `;
@@ -1572,9 +1562,7 @@ else {
 if (10) {
   /* comment */ // comment
   true;
-} else if (11)
-  /* comment */
-  true;
+} else if (11) /* comment */ true;
 else if (12)
   // comment /* comment */ // comment
   true;
@@ -1721,9 +1709,7 @@ else {
 if (10) {
   /* comment */ // comment
   true
-} else if (11)
-  /* comment */
-  true
+} else if (11) /* comment */ true
 else if (12)
   // comment /* comment */ // comment
   true
diff --git a/tests/comments_closure_typecast/__snapshots__/jsfmt.spec.js.snap b/tests/comments_closure_typecast/__snapshots__/jsfmt.spec.js.snap
index 3fcc5c771..dd6c8517e 100644
--- a/tests/comments_closure_typecast/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/comments_closure_typecast/__snapshots__/jsfmt.spec.js.snap
@@ -78,6 +78,9 @@ const v6 = /**@type {string} */(value);
 const v7 = /** @type{string} */(value);
 const v8 = /**@type{string} */(value);
 
+const v9 = /** @type {string} */
+  (value);
+
 =====================================output=====================================
 // test to make sure comments are attached correctly
 let inlineComment = /* some comment */ someReallyLongFunctionCall(
@@ -154,6 +157,8 @@ const v6 = /**@type {string} */ (value);
 const v7 = /** @type{string} */ (value);
 const v8 = /**@type{string} */ (value);
 
+const v9 = /** @type {string} */ (value);
+
 ================================================================================
 `;
 
diff --git a/tests/comments_closure_typecast/closure-compiler-type-cast.js b/tests/comments_closure_typecast/closure-compiler-type-cast.js
index 585e92b0f..c84833dc5 100644
--- a/tests/comments_closure_typecast/closure-compiler-type-cast.js
+++ b/tests/comments_closure_typecast/closure-compiler-type-cast.js
@@ -69,3 +69,6 @@ const style2 =/**
 const v6 = /**@type {string} */(value);
 const v7 = /** @type{string} */(value);
 const v8 = /**@type{string} */(value);
+
+const v9 = /** @type {string} */
+  (value);
diff --git a/tests/if/__snapshots__/jsfmt.spec.js.snap b/tests/if/__snapshots__/jsfmt.spec.js.snap
index a9885f619..859bd5b94 100644
--- a/tests/if/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/if/__snapshots__/jsfmt.spec.js.snap
@@ -162,15 +162,9 @@ async function f1() {
 }
 
 async function f2() {
-  if (untrackedChoice === 0)
-    /* Cancel */
-    null;
-  else if (untrackedChoice === 1)
-    /* Add */
-    shouldAmend = true;
-  else if (untrackedChoice === 2)
-    /* Allow Untracked */
-    allowUntracked = true;
+  if (untrackedChoice === 0) /* Cancel */ null;
+  else if (untrackedChoice === 1) /* Add */ shouldAmend = true;
+  else if (untrackedChoice === 2) /* Allow Untracked */ allowUntracked = true;
 }
 
 async function f3() {