diff --git a/src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/SerializedFrozenObjectNode.cs b/src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/SerializedFrozenObjectNode.cs
index fbe021414800bc..f3bb469c986942 100644
--- a/src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/SerializedFrozenObjectNode.cs
+++ b/src/coreclr/tools/aot/ILCompiler.Compiler/Compiler/DependencyAnalysis/SerializedFrozenObjectNode.cs
@@ -34,6 +34,7 @@ public override void AppendMangledName(NameMangler nameMangler, Utf8StringBuilde
         {
             sb.Append(nameMangler.CompilationUnitPrefix).Append("__FrozenObj_"u8)
                 .Append(nameMangler.GetMangledTypeName(_owningType))
+                .Append('_')
                 .Append(_allocationSiteId.ToStringInvariant());
         }