diff --git a/Editor/ObfusPasses/CallObfus/CallObfusPass.cs b/Editor/ObfusPasses/CallObfus/CallObfusPass.cs
index 5527337..8cc37dc 100644
--- a/Editor/ObfusPasses/CallObfus/CallObfusPass.cs
+++ b/Editor/ObfusPasses/CallObfus/CallObfusPass.cs
@@ -93,10 +93,10 @@ namespace Obfuz.ObfusPasses.CallObfus
 
         private bool ComputeIsInWhiteList(IMethod calledMethod)
         {
+            MethodDef calledMethodDef = calledMethod.ResolveMethodDef();
             // mono has more strict access control, calls non-public method will raise exception.
             if (PlatformUtil.IsMonoBackend())
             {
-                MethodDef calledMethodDef = calledMethod.ResolveMethodDef();
                 if (calledMethodDef != null && (!calledMethodDef.IsPublic || !IsTypeSelfAndParentPublic(calledMethodDef.DeclaringType)))
                 {
                     return true;
@@ -125,6 +125,12 @@ namespace Obfuz.ObfusPasses.CallObfus
             }
 
             TypeDef typeDef = declaringType.ResolveTypeDef();
+
+            if (!_settings.obfuscateCallToMethodInMscorlib && typeDef.Module.IsCoreLibraryModule == true)
+            {
+                return true;
+            }
+
             if (typeDef.IsDelegate || typeDef.IsEnum)
                 return true;
 
diff --git a/Editor/Settings/CallObfuscationSettings.cs b/Editor/Settings/CallObfuscationSettings.cs
index 3bc2150..983a32f 100644
--- a/Editor/Settings/CallObfuscationSettings.cs
+++ b/Editor/Settings/CallObfuscationSettings.cs
@@ -10,6 +10,7 @@ namespace Obfuz.Settings
         public List<string> ruleFiles;
         public int obfuscationLevel;
         public int maxProxyMethodCountPerDispatchMethod;
+        public bool obfuscateCallToMethodInMscorlib;
     }
 
     [Serializable]
@@ -22,6 +23,9 @@ namespace Obfuz.Settings
         [Tooltip("The maximum number of proxy methods that can be generated per dispatch method. This helps to limit the complexity of the generated code and improve performance.")]
         public int maxProxyMethodCountPerDispatchMethod = 100;
 
+        [Tooltip("Whether to obfuscate calls to methods in mscorlib. This can help to protect against reverse engineering, but may cause compatibility issues with some libraries.")]
+        public bool obfuscateCallToMethodInMscorlib;
+
         [Tooltip("rule config xml files")]
         public string[] ruleFiles;
 
@@ -32,6 +36,7 @@ namespace Obfuz.Settings
                 ruleFiles = ruleFiles?.ToList() ?? new List<string>(),
                 obfuscationLevel = obfuscationLevel,
                 maxProxyMethodCountPerDispatchMethod = maxProxyMethodCountPerDispatchMethod,
+                obfuscateCallToMethodInMscorlib = obfuscateCallToMethodInMscorlib,
             };
         }
     }