diff --git a/src/hotspot/share/memory/heapInspection.cpp b/src/hotspot/share/memory/heapInspection.cpp
index 385bf8ff6dd..4161035ac6c 100644
--- a/src/hotspot/share/memory/heapInspection.cpp
+++ b/src/hotspot/share/memory/heapInspection.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -597,10 +597,15 @@ void PrintClassLayout::print_class_layout(outputStream* st, char* class_name) {
     return;
   }
 
+  for (char* p = class_name; *p != '\0'; p++) {
+    if (*p == JVM_SIGNATURE_DOT) {
+      *p = JVM_SIGNATURE_SLASH;
+    }
+  }
+
   Symbol* classname = SymbolTable::probe(class_name, (int)strlen(class_name));
 
   GrowableArray<Klass*>* klasses = new (mtServiceability) GrowableArray<Klass*>(100, mtServiceability);
-
   FindClassByNameClosure fbnc(klasses, classname);
   cit.iterate(&fbnc);
 
@@ -608,9 +613,9 @@ void PrintClassLayout::print_class_layout(outputStream* st, char* class_name) {
     Klass* klass = klasses->at(i);
     if (!klass->is_instance_klass()) continue;  // Skip
     InstanceKlass* ik = InstanceKlass::cast(klass);
-    st->print_cr("Class %s [@%s]:", klass->name()->as_C_string(),
-        klass->class_loader_data()->loader_name());
     ResourceMark rm;
+    st->print_cr("Class %s [@%s]:", klass->external_name(),
+                 klass->class_loader_data()->loader_name());
     GrowableArray<FieldDesc>* fields = new (mtServiceability) GrowableArray<FieldDesc>(100, mtServiceability);
     for (AllFieldStream fd(ik); !fd.done(); fd.next()) {
       if (!fd.access_flags().is_static()) {
diff --git a/test/hotspot/jtreg/runtime/valhalla/inlinetypes/ClassPrintLayoutDcmd.java b/test/hotspot/jtreg/runtime/valhalla/inlinetypes/ClassPrintLayoutDcmd.java
index afbe6e2182f..e792fea3422 100644
--- a/test/hotspot/jtreg/runtime/valhalla/inlinetypes/ClassPrintLayoutDcmd.java
+++ b/test/hotspot/jtreg/runtime/valhalla/inlinetypes/ClassPrintLayoutDcmd.java
@@ -81,10 +81,10 @@ static void testCmd(String arg, int expectExitCode, String... expectStrings) thr
     }
 
     public static void main(String args[]) throws Exception {
-        testCmd("foo/bar", 0, "");
+        testCmd("foo.bar", 0, "");
         testCmd("", 1, "IllegalArgumentException", "mandatory");
-        testCmd("java/lang/Object", 0, "java/lang/Object", "@bootstrap");
-        testCmd("java/lang/Class", 0, "java/lang/Class", "@bootstrap");
-        testCmd("runtime/valhalla/inlinetypes/ClassPrintLayoutDcmd$Line", 0, "@app", "p1", "p2");
+        testCmd("java.lang.Object", 0, "java.lang.Object", "@bootstrap");
+        testCmd("java.lang.Class", 0, "java.lang.Class", "@bootstrap");
+        testCmd("runtime.valhalla.inlinetypes.ClassPrintLayoutDcmd$Line", 0, "@app", "p1", "p2");
     }
 }