diff --git a/CHANGES.md b/CHANGES.md
index 5570328a49..26689bc82a 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -16,6 +16,7 @@
 * Compiler: fix global flow analysis (#1494)
 * Compiler: fix js parser/printer wrt async functions (#1515)
 * Compiler: fix free variables pass wrt parameters' default value (#1521)
+* Compiler: fix free variables for classes
 
 # 5.4.0 (2023-07-06) - Lille
 
diff --git a/compiler/lib/js_traverse.ml b/compiler/lib/js_traverse.ml
index 8553a4f581..32413be9cc 100644
--- a/compiler/lib/js_traverse.ml
+++ b/compiler/lib/js_traverse.ml
@@ -842,6 +842,15 @@ class free =
           tbody#record_block (Params params);
           m#merge_info tbody;
           EFun (ident, (k, params, body, nid))
+      | EClass (ident_o, cl_decl) ->
+          let ident_o =
+            Option.map
+              ~f:(fun id ->
+                m#def_var id;
+                m#ident id)
+              ident_o
+          in
+          EClass (ident_o, m#class_decl cl_decl)
       | _ -> super#expression x
 
     method record_block _ = ()
@@ -873,6 +882,9 @@ class free =
           m#def_var id;
           m#merge_info tbody;
           Function_declaration (id, (k, params, body, nid))
+      | Class_declaration (id, cl_decl) ->
+          m#def_var id;
+          Class_declaration (id, m#class_decl cl_decl)
       | Block b -> Block (m#block b)
       | Try_statement (b, w, f) ->
           let same_level = level in
@@ -946,7 +958,12 @@ class rename_variable =
 
        inherit iter as super
 
-       method expression _ = ()
+       method expression e =
+         match e with
+         | EClass (ido, _) ->
+             Option.iter ido ~f:decl_var;
+             super#expression e
+         | _ -> super#expression e
 
        method fun_decl _ = ()
 
@@ -956,6 +973,9 @@ class rename_variable =
              decl_var id;
              self#fun_decl fd
          | Lexical_block, Function_declaration (_, fd) -> self#fun_decl fd
+         | (Fun_block _ | Lexical_block), Class_declaration (id, _) ->
+             decl_var id;
+             super#statement x
          | (Fun_block _ | Lexical_block), _ -> super#statement x
 
        method variable_declaration k l =
diff --git a/compiler/tests-compiler/minify.ml b/compiler/tests-compiler/minify.ml
index ada53d028f..6b2f6f8b8d 100644
--- a/compiler/tests-compiler/minify.ml
+++ b/compiler/tests-compiler/minify.ml
@@ -304,8 +304,8 @@ let%expect_test _ =
       let js_prog =
         {|
 (function () {
-  class f {
-    f() {
+  class longname {
+    longname() {
       const y = 2;
       return v
     }
@@ -327,8 +327,8 @@ let%expect_test _ =
         $ cat "test.js"
           1:
           2: (function () {
-          3:   class f {
-          4:     f() {
+          3:   class longname {
+          4:     longname() {
           5:       const y = 2;
           6:       return v
           7:     }
@@ -338,9 +338,9 @@ let%expect_test _ =
          11:
         $ cat "test.min.js"
           1: (function(){class
-          2: f{f(){const
+          2: a{longname(){const
           3: a=2;return v}}const
-          4: a=y}()); |}])
+          4: b=y}()); |}])
 
 let%expect_test _ =
   with_temp_dir ~f:(fun () ->