diff --git a/Assets/VRM/Tests/VRMTextureEnumerateTests.cs b/Assets/VRM/Tests/VRMTextureEnumerateTests.cs
index 80a9d80cf..f7d602a61 100644
--- a/Assets/VRM/Tests/VRMTextureEnumerateTests.cs
+++ b/Assets/VRM/Tests/VRMTextureEnumerateTests.cs
@@ -76,5 +76,60 @@ namespace VRM
                 Assert.AreEqual(1, items.Length);
             }
         }
+
+        [Test]
+        public void TextureEnumerationInUnknownShader()
+        {
+            var parser = new GltfParser
+            {
+                GLTF = new glTF
+                {
+                    images = new List<glTFImage>
+                        {
+                            new glTFImage{
+                                mimeType = "image/png",
+                            }
+                        },
+                    textures = new List<glTFTexture>
+                        {
+                            new glTFTexture{
+                                name = "texture0",
+                                source = 0,
+                            }
+                        },
+                    materials = new List<glTFMaterial>
+                        {
+                            new glTFMaterial{
+                                pbrMetallicRoughness = new glTFPbrMetallicRoughness{
+                                    baseColorTexture = new glTFMaterialBaseColorTextureInfo{
+                                        index = 0,
+                                    }
+                                }
+                            },
+                        }
+                }
+            };
+            var vrm = new glTF_VRM_extensions
+            {
+                materialProperties = new List<glTF_VRM_Material>
+                    {
+                        new glTF_VRM_Material
+                        {
+                            shader = "UnknownShader",
+                            textureProperties = new Dictionary<string, int>
+                            {
+                                {"_MainTex", 0},
+                            }
+                        },
+                     }
+            };
+
+            // 2系統ある？
+            Assert.IsTrue(VRMMToonMaterialImporter.TryCreateParam(parser, vrm, 0, out VRMShaders.MaterialDescriptor matDesc));
+            Assert.AreEqual(1, matDesc.TextureSlots.Count);
+
+            var items = new VrmTextureDescriptorGenerator(parser, vrm).Get().GetEnumerable().ToArray();
+            Assert.AreEqual(1, items.Length);
+        }
     }
 }