diff --git a/Assets/UniGLTF/Editor/UniGLTF/ExportDialog/MaterialValidator.cs b/Assets/UniGLTF/Editor/UniGLTF/ExportDialog/MaterialValidator.cs
index 93732b958..bf6d15af4 100644
--- a/Assets/UniGLTF/Editor/UniGLTF/ExportDialog/MaterialValidator.cs
+++ b/Assets/UniGLTF/Editor/UniGLTF/ExportDialog/MaterialValidator.cs
@@ -43,12 +43,26 @@ namespace UniGLTF
             // main color
             yield return (MaterialExporter.COLOR_TEXTURE_PROP, m.GetTexture(MaterialExporter.COLOR_TEXTURE_PROP));
 
-            if (GetGltfMaterialTypeFromUnityShaderName(m.shader.name) == "Standard")
+            if (GetGltfMaterialTypeFromUnityShaderName(m.shader.name) == "unlit")
+            {
+                yield break;
+            }
+
+            // PBR
+            if (m.HasProperty(MaterialExporter.METALLIC_TEX_PROP))
             {
-                // PBR
                 yield return (MaterialExporter.METALLIC_TEX_PROP, m.GetTexture(MaterialExporter.METALLIC_TEX_PROP));
+            }
+            if (m.HasProperty(MaterialExporter.NORMAL_TEX_PROP))
+            {
                 yield return (MaterialExporter.NORMAL_TEX_PROP, m.GetTexture(MaterialExporter.NORMAL_TEX_PROP));
+            }
+            if (m.HasProperty(MaterialExporter.EMISSION_TEX_PROP))
+            {
                 yield return (MaterialExporter.EMISSION_TEX_PROP, m.GetTexture(MaterialExporter.EMISSION_TEX_PROP));
+            }
+            if (m.HasProperty(MaterialExporter.OCCLUSION_TEX_PROP))
+            {
                 yield return (MaterialExporter.OCCLUSION_TEX_PROP, m.GetTexture(MaterialExporter.OCCLUSION_TEX_PROP));
             }
         }