diff --git a/Assets/UniGLTF/Runtime/UniGLTF/IO/BufferAccessor.cs b/Assets/UniGLTF/Runtime/UniGLTF/IO/BufferAccessor.cs
index 43e4a6273..6ead44a56 100644
--- a/Assets/UniGLTF/Runtime/UniGLTF/IO/BufferAccessor.cs
+++ b/Assets/UniGLTF/Runtime/UniGLTF/IO/BufferAccessor.cs
@@ -157,6 +157,9 @@ namespace UniGLTF
             }
             switch (ComponentType)
             {
+                case AccessorValueType.UNSIGNED_BYTE:
+                    return ArrayManager.Convert(Bytes, (byte x) => (int)x);
+
                 case AccessorValueType.UNSIGNED_SHORT:
                     return ArrayManager.Convert(Bytes.Reinterpret<ushort>(1), (ushort x) => (int)x);
 
diff --git a/Assets/VRM10/Runtime/IO/Model/MeshImporter.cs b/Assets/VRM10/Runtime/IO/Model/MeshImporter.cs
index d27a78e76..035fdd7df 100644
--- a/Assets/VRM10/Runtime/IO/Model/MeshImporter.cs
+++ b/Assets/VRM10/Runtime/IO/Model/MeshImporter.cs
@@ -65,16 +65,27 @@ namespace UniVRM10
             // Indexを更新
             switch (src.IndexBuffer.ComponentType)
             {
+                case AccessorValueType.UNSIGNED_BYTE:
+                    {
+                        var intIndices = src.IndexBuffer.GetAsIntArray();
+                        mesh.SetIndexBufferParams(intIndices.Length, IndexFormat.UInt32);
+                        mesh.SetIndexBufferData(intIndices, 0, 0, intIndices.Length);
+                        break;
+                    }
                 case AccessorValueType.UNSIGNED_SHORT:
-                    var shortIndices = src.IndexBuffer.Bytes.Reinterpret<ushort>(1);
-                    mesh.SetIndexBufferParams(shortIndices.Length, IndexFormat.UInt16);
-                    mesh.SetIndexBufferData(shortIndices, 0, 0, shortIndices.Length);
-                    break;
+                    {
+                        var shortIndices = src.IndexBuffer.Bytes.Reinterpret<ushort>(1);
+                        mesh.SetIndexBufferParams(shortIndices.Length, IndexFormat.UInt16);
+                        mesh.SetIndexBufferData(shortIndices, 0, 0, shortIndices.Length);
+                        break;
+                    }
                 case AccessorValueType.UNSIGNED_INT:
-                    var intIndices = src.IndexBuffer.Bytes.Reinterpret<uint>(1);
-                    mesh.SetIndexBufferParams(intIndices.Length, IndexFormat.UInt32);
-                    mesh.SetIndexBufferData(intIndices, 0, 0, intIndices.Length);
-                    break;
+                    {
+                        var intIndices = src.IndexBuffer.Bytes.Reinterpret<uint>(1);
+                        mesh.SetIndexBufferParams(intIndices.Length, IndexFormat.UInt32);
+                        mesh.SetIndexBufferData(intIndices, 0, 0, intIndices.Length);
+                        break;
+                    }
                 default:
                     throw new NotImplementedException();
             }
@@ -101,6 +112,10 @@ namespace UniVRM10
             // 各種パラメーターを再計算
             mesh.RecalculateBounds();
             mesh.RecalculateTangents();
+            if (src.VertexBuffer.Normals == null)
+            {
+                mesh.RecalculateNormals();
+            }
 
             Profiler.EndSample();
 
diff --git a/Assets/VRM10/Runtime/IO/Model/MeshImporterDivided.cs b/Assets/VRM10/Runtime/IO/Model/MeshImporterDivided.cs
index 91d71c6e9..49de5fc71 100644
--- a/Assets/VRM10/Runtime/IO/Model/MeshImporterDivided.cs
+++ b/Assets/VRM10/Runtime/IO/Model/MeshImporterDivided.cs
@@ -42,6 +42,10 @@ namespace UniVRM10
             // 各種データを再構築
             resultMesh.RecalculateBounds();
             resultMesh.RecalculateTangents();
+            if (meshGroup.Meshes.Any(mesh => mesh.VertexBuffer.Normals == null))
+            {
+                resultMesh.RecalculateNormals();
+            }
 
             // BlendShapeを更新
             var blendShapeCount = meshGroup.Meshes[0].MorphTargets.Count;
diff --git a/Assets/VRM10/Runtime/IO/Model/MeshReader.cs b/Assets/VRM10/Runtime/IO/Model/MeshReader.cs
index 9a5383ec1..cd99b6896 100644
--- a/Assets/VRM10/Runtime/IO/Model/MeshReader.cs
+++ b/Assets/VRM10/Runtime/IO/Model/MeshReader.cs
@@ -67,6 +67,13 @@ namespace UniVRM10
                 mesh.IndexBuffer = storage.CreateAccessor(primitive.indices);
             }
 
+            if (mesh.IndexBuffer == null)
+            {
+                var indices = Enumerable.Range(0, mesh.VertexBuffer.Count).ToArray();
+                var na = storage.Data.NativeArrayManager.CreateNativeArray(indices);
+                mesh.IndexBuffer = new BufferAccessor(storage.Data.NativeArrayManager, na.Reinterpret<byte>(4), AccessorValueType.UNSIGNED_INT, AccessorVectorType.SCALAR, na.Length);
+            }
+
             {
                 gltf_mesh_extras_targetNames.TryGet(x, out List<string> targetNames);
 
diff --git a/Assets/VRM10/Runtime/IO/Vrm10ImportData.cs b/Assets/VRM10/Runtime/IO/Vrm10ImportData.cs
index c174a3d62..ada4c16f8 100644
--- a/Assets/VRM10/Runtime/IO/Vrm10ImportData.cs
+++ b/Assets/VRM10/Runtime/IO/Vrm10ImportData.cs
@@ -12,6 +12,7 @@ namespace UniVRM10
     public class Vrm10ImportData
     {
         UniGLTF.GltfData m_data;
+        public UniGLTF.GltfData Data => m_data;
 
         public UniGLTF.glTF Gltf => m_data.GLTF;
         public string AssetVersion => Gltf.asset.version;
@@ -363,12 +364,7 @@ namespace UniVRM10
                 if (x.translation != null && x.translation.Length > 0) throw new Exception("matrix with translation");
                 if (x.rotation != null && x.rotation.Length > 0) throw new Exception("matrix with rotation");
                 if (x.scale != null && x.scale.Length > 0) throw new Exception("matrix with scale");
-                var m = new Matrix4x4(
-                    new Vector4(x.matrix[0], x.matrix[4], x.matrix[8], x.matrix[12]),
-                    new Vector4(x.matrix[1], x.matrix[5], x.matrix[9], x.matrix[13]),
-                    new Vector4(x.matrix[2], x.matrix[6], x.matrix[10], x.matrix[14]),
-                    new Vector4(x.matrix[3], x.matrix[7], x.matrix[11], x.matrix[15])
-                    );
+                var m = UnityExtensions.MatrixFromArray(x.matrix);
 
                 node.SetLocalMatrix(m, true);
             }