diff --git a/Generate-ReleaseNotes.bat b/Generate-ReleaseNotes.bat
index cb1804a..e3881de 100644
--- a/Generate-ReleaseNotes.bat
+++ b/Generate-ReleaseNotes.bat
@@ -1,6 +1,6 @@
 rem https://github.com/StefH/GitHubReleaseNotes
 
-SET version=0.0.30
+SET version=0.0.31
 
 GitHubReleaseNotes --output "ReleaseNotes.md" --skip-empty-releases --exclude-labels question invalid doc --version %version%
 
diff --git a/src/ProxyInterfaceSourceGenerator/Builders/MethodParameterBuilder.cs b/src/ProxyInterfaceSourceGenerator/Builders/MethodParameterBuilder.cs
index e7cec8a..b3871c3 100644
--- a/src/ProxyInterfaceSourceGenerator/Builders/MethodParameterBuilder.cs
+++ b/src/ProxyInterfaceSourceGenerator/Builders/MethodParameterBuilder.cs
@@ -9,7 +9,7 @@ internal static class MethodParameterBuilder
     public static string Build(IParameterSymbol parameterSymbol, string? type)
     {
         var stringBuilder = new StringBuilder();
-        if (type is { })
+        if (type is not null)
         {
             stringBuilder.Append(parameterSymbol.GetAttributesPrefix()); // "" or [NotNullWhen(true)]
             stringBuilder.Append(parameterSymbol.GetParamsPrefix()); // "" or "params "
diff --git a/src/ProxyInterfaceSourceGenerator/FileGenerators/BaseGenerator.cs b/src/ProxyInterfaceSourceGenerator/FileGenerators/BaseGenerator.cs
index 24957f5..c7c8aa4 100644
--- a/src/ProxyInterfaceSourceGenerator/FileGenerators/BaseGenerator.cs
+++ b/src/ProxyInterfaceSourceGenerator/FileGenerators/BaseGenerator.cs
@@ -11,6 +11,8 @@ namespace ProxyInterfaceSourceGenerator.FileGenerators;
 
 internal abstract class BaseGenerator
 {
+    private const string Star = "*";
+
     protected readonly Context Context;
     protected readonly bool SupportsNullable;
 
@@ -150,7 +152,7 @@ internal abstract class BaseGenerator
             }
 
             isReplaced = true;
-            return existing.FullInterfaceName;
+            return FixType(existing.FullInterfaceName);
         }
 
         ITypeSymbol[] typeArguments;
@@ -164,7 +166,7 @@ internal abstract class BaseGenerator
         }
         else
         {
-            return typeSymbolAsString;
+            return FixType(typeSymbolAsString);
         }
 
         var propertyTypeAsStringToBeModified = typeSymbolAsString;
@@ -185,7 +187,7 @@ internal abstract class BaseGenerator
             }
         }
 
-        return propertyTypeAsStringToBeModified;
+        return FixType(propertyTypeAsStringToBeModified);
     }
 
     protected bool TryGetNamedTypeSymbolByFullName(TypeKind kind, string name, IEnumerable<string> usings, [NotNullWhen(true)] out ClassSymbol? classSymbol)
@@ -258,4 +260,13 @@ internal abstract class BaseGenerator
         }
         return extendsProxyClasses;
     }
+
+    /// <summary>
+    /// Issue 54
+    /// double[*,*] --> double[,]
+    /// </summary>
+    protected static string FixType(string type)
+    {
+        return type.Replace(Star, string.Empty);
+    }
 }
\ No newline at end of file
diff --git a/src/ProxyInterfaceSourceGenerator/FileGenerators/ProxyClassesGenerator.cs b/src/ProxyInterfaceSourceGenerator/FileGenerators/ProxyClassesGenerator.cs
index 176a28e..9ecfa8b 100644
--- a/src/ProxyInterfaceSourceGenerator/FileGenerators/ProxyClassesGenerator.cs
+++ b/src/ProxyInterfaceSourceGenerator/FileGenerators/ProxyClassesGenerator.cs
@@ -235,6 +235,7 @@ using System;
             str.AppendLine("        {");
             foreach (var ps in method.Parameters)
             {
+                var type = FixType(ps.Type.ToString());
                 string normalOrMap = $" = {ps.GetSanitizedName()}";
                 if (ps.RefKind == RefKind.Out)
                 {
@@ -245,11 +246,11 @@ using System;
                     _ = GetParameterType(ps, out var isReplaced); // TODO : response is not used?
                     if (isReplaced)
                     {
-                        normalOrMap = $" = Mapster.TypeAdapter.Adapt<{ps.Type}>({ps.GetSanitizedName()})";
+                        normalOrMap = $" = Mapster.TypeAdapter.Adapt<{type}>({ps.GetSanitizedName()})";
                     }
                 }
 
-                str.AppendLine($"            {ps.Type} {ps.GetSanitizedName()}_{normalOrMap};");
+                str.AppendLine($"            {type} {ps.GetSanitizedName()}_{normalOrMap};");
             }
 
             var methodName = method.GetMethodNameWithOptionalTypeParameters();
diff --git a/src/ProxyInterfaceSourceGenerator/ProxyInterfaceSourceGenerator.csproj b/src/ProxyInterfaceSourceGenerator/ProxyInterfaceSourceGenerator.csproj
index 66f3306..c88d5f1 100644
--- a/src/ProxyInterfaceSourceGenerator/ProxyInterfaceSourceGenerator.csproj
+++ b/src/ProxyInterfaceSourceGenerator/ProxyInterfaceSourceGenerator.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <Version>0.0.30</Version>
+        <Version>0.0.31</Version>
         <TargetFramework>netstandard2.0</TargetFramework>
         <ProjectGuid>{12344228-91F4-4502-9595-39584E5ABB34}</ProjectGuid>
         <LangVersion>10</LangVersion>
diff --git a/tests/ProxyInterfaceSourceGeneratorTests/Destination/ProxyInterfaceSourceGeneratorTests.Source.IPerson.g.cs b/tests/ProxyInterfaceSourceGeneratorTests/Destination/ProxyInterfaceSourceGeneratorTests.Source.IPerson.g.cs
index 7821db8..a2b49a4 100644
--- a/tests/ProxyInterfaceSourceGeneratorTests/Destination/ProxyInterfaceSourceGeneratorTests.Source.IPerson.g.cs
+++ b/tests/ProxyInterfaceSourceGeneratorTests/Destination/ProxyInterfaceSourceGeneratorTests.Source.IPerson.g.cs
@@ -54,6 +54,8 @@ namespace ProxyInterfaceSourceGeneratorTests.Source
 
         void In_Out_Ref1(in int a, out int b, ref int c);
 
+        double[,] Out_MultiDimensionIssue54(out double[,] x);
+
         bool Generic2<T1, T2>(int x, T1 t1, T2 t2) where T1 : struct where T2 : class, new();
 
         System.Threading.Tasks.Task Method1Async();
diff --git a/tests/ProxyInterfaceSourceGeneratorTests/Destination/ProxyInterfaceSourceGeneratorTests.Source.PersonProxy.g.cs b/tests/ProxyInterfaceSourceGeneratorTests/Destination/ProxyInterfaceSourceGeneratorTests.Source.PersonProxy.g.cs
index 3f8357e..094cd9b 100644
--- a/tests/ProxyInterfaceSourceGeneratorTests/Destination/ProxyInterfaceSourceGeneratorTests.Source.PersonProxy.g.cs
+++ b/tests/ProxyInterfaceSourceGeneratorTests/Destination/ProxyInterfaceSourceGeneratorTests.Source.PersonProxy.g.cs
@@ -110,6 +110,14 @@ namespace ProxyInterfaceSourceGeneratorTests.Source
             b = b_;
         }
 
+        public double[,] Out_MultiDimensionIssue54(out double[,] x)
+        {
+            double[,] x_;
+            var result_692039870 = _Instance.Out_MultiDimensionIssue54(out x_);
+            x = x_;
+            return result_692039870;
+        }
+
         public bool Generic2<T1, T2>(int x, T1 t1, T2 t2) where T1 : struct where T2 : class, new()
         {
             int x_ = x;
diff --git a/tests/ProxyInterfaceSourceGeneratorTests/Source/Person.cs b/tests/ProxyInterfaceSourceGeneratorTests/Source/Person.cs
index 6123cf6..8d9a138 100644
--- a/tests/ProxyInterfaceSourceGeneratorTests/Source/Person.cs
+++ b/tests/ProxyInterfaceSourceGeneratorTests/Source/Person.cs
@@ -85,6 +85,12 @@ namespace ProxyInterfaceSourceGeneratorTests.Source
             b = 1;
         }
 
+        public double[,] Out_MultiDimensionIssue54(out double[,] x)
+        {
+            x = new double[0, 0];
+            return x;
+        }
+
         public bool Generic2<T1, T2>(int x, T1 t1, T2 t2)
             where T1 : struct
             where T2 : class, new()