diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/Import/MaterialFactory.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/Import/MaterialFactory.cs
index ab4d0955b..518280865 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/Import/MaterialFactory.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/MaterialIO/Import/MaterialFactory.cs
@@ -14,20 +14,22 @@ namespace UniGLTF
         private readonly MaterialDescriptor m_defaultMaterialParams;
         private readonly List<MaterialLoadInfo> m_materials = new List<MaterialLoadInfo>();
 
-        /// <summary>
-        /// gltfPritmitive.material が無い場合のデフォルトマテリアル
-        /// https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#default-material
-        ///
-        /// </summary>
-        private Material m_defaultMaterial;
-
         public IReadOnlyList<MaterialLoadInfo> Materials => m_materials;
 
-
         public MaterialFactory(IReadOnlyDictionary<SubAssetKey, Material> externalMaterialMap, MaterialDescriptor defaultMaterialParams)
         {
             m_externalMap = externalMaterialMap;
-            m_defaultMaterialParams = defaultMaterialParams;
+            m_defaultMaterialParams = new MaterialDescriptor(
+                m_defaultMaterialKey.Name,
+                defaultMaterialParams.Shader,
+                defaultMaterialParams.RenderQueue,
+                defaultMaterialParams.TextureSlots,
+                defaultMaterialParams.FloatValues,
+                defaultMaterialParams.Colors,
+                defaultMaterialParams.Vectors,
+                defaultMaterialParams.Actions,
+                defaultMaterialParams.AsyncActions
+            );
         }
 
         public struct MaterialLoadInfo
@@ -56,11 +58,6 @@ namespace UniGLTF
                     UnityObjectDestroyer.DestroyRuntimeOrEditor(x.Asset);
                 }
             }
-
-            if (m_defaultMaterial != null)
-            {
-                UnityObjectDestroyer.DestroyRuntimeOrEditor(m_defaultMaterial);
-            }
         }
 
         /// <summary>
@@ -84,12 +81,6 @@ namespace UniGLTF
                     m_materials.Remove(x);
                 }
             }
-
-            if (m_defaultMaterial != null)
-            {
-                take(m_defaultMaterialKey, m_defaultMaterial);
-                m_defaultMaterial = null;
-            }
         }
 
         public Material GetMaterial(int index)
@@ -99,22 +90,16 @@ namespace UniGLTF
             return m_materials[index].Asset;
         }
 
-        public async Task<Material> GetDefaultMaterialAsync(IAwaitCaller awaitCaller)
+        /// <summary>
+        /// gltfPritmitive.material が無い場合のデフォルトマテリアル
+        /// https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#default-material
+        ///
+        /// </summary>
+        public Task<Material> GetDefaultMaterialAsync(IAwaitCaller awaitCaller)
         {
-            if (m_externalMap.ContainsKey(m_defaultMaterialKey))
-            {
-                m_defaultMaterial = m_externalMap[m_defaultMaterialKey];
-                return m_externalMap[m_defaultMaterialKey];
-            }
-
-            if (m_defaultMaterial == null)
-            {
-                m_defaultMaterial = await LoadAsync(m_defaultMaterialParams, (_, _) => null, awaitCaller);
-            }
-            return m_defaultMaterial;
+            return LoadAsync(m_defaultMaterialParams, (_, _) => null, awaitCaller);
         }
 
-
         public async Task<Material> LoadAsync(MaterialDescriptor matDesc, GetTextureAsyncFunc getTexture, IAwaitCaller awaitCaller)
         {
             if (m_externalMap.TryGetValue(matDesc.SubAssetKey, out Material material))