diff --git a/packages/babel-generator/src/generators/methods.ts b/packages/babel-generator/src/generators/methods.ts
index 5efd17a53582..4cfeaf151c16 100644
--- a/packages/babel-generator/src/generators/methods.ts
+++ b/packages/babel-generator/src/generators/methods.ts
@@ -184,7 +184,7 @@ export function ArrowFunctionExpression(
     !this.format.retainLines &&
     node.params.length === 1 &&
     isIdentifier((firstParam = node.params[0])) &&
-    !hasTypes(node, firstParam)
+    !hasTypesOrComments(node, firstParam)
   ) {
     this.print(firstParam, node);
     this._noLineTerminator = _noLineTerminator;
@@ -205,7 +205,7 @@ export function ArrowFunctionExpression(
   this.print(node.body, node);
 }
 
-function hasTypes(
+function hasTypesOrComments(
   node: t.ArrowFunctionExpression,
   param: t.Identifier,
 ): boolean {
@@ -214,6 +214,9 @@ function hasTypes(
     node.returnType ||
     node.predicate ||
     param.typeAnnotation ||
-    param.optional
+    param.optional ||
+    // Flow does not support `foo /*: string*/ => {};`
+    param.leadingComments?.length ||
+    param.trailingComments?.length
   );
 }
diff --git a/packages/babel-generator/test/fixtures/comments/async-arrow-single-param-with-comments/output.js b/packages/babel-generator/test/fixtures/comments/async-arrow-single-param-with-comments/output.js
index a1e62b4e986f..addc834ee0ed 100644
--- a/packages/babel-generator/test/fixtures/comments/async-arrow-single-param-with-comments/output.js
+++ b/packages/babel-generator/test/fixtures/comments/async-arrow-single-param-with-comments/output.js
@@ -1,3 +1,3 @@
-async /** @type {any} */arg => {};
-async arg /* trailing */ => {};
-async /** @type {any} */arg /* trailing */ => {};
\ No newline at end of file
+async ( /** @type {any} */arg) => {};
+async (arg /* trailing */) => {};
+async ( /** @type {any} */arg /* trailing */) => {};
\ No newline at end of file
diff --git a/packages/babel-generator/test/fixtures/parentheses/async-arrow-function/output.js b/packages/babel-generator/test/fixtures/parentheses/async-arrow-function/output.js
index f718e264aefc..bf33d2ca48fc 100644
--- a/packages/babel-generator/test/fixtures/parentheses/async-arrow-function/output.js
+++ b/packages/babel-generator/test/fixtures/parentheses/async-arrow-function/output.js
@@ -1,6 +1,6 @@
-const x = async
-/* some comment*/
-a => {
+const x = async (
+// some comment
+a) => {
   return foo(await a);
 };
 function foo(a) {