diff --git a/Scripts/Format/VRMExporter.cs b/Scripts/Format/VRMExporter.cs
index f625a094f..b3a0f7147 100644
--- a/Scripts/Format/VRMExporter.cs
+++ b/Scripts/Format/VRMExporter.cs
@@ -30,6 +30,13 @@ namespace VRM
                     exporter.WriteTo(path);
                 }
             }
+
+            // update buffer size
+            foreach (var b in gltf.buffers)
+            {
+                b.UpdateByteLength();
+            }
+
             return gltf;
         }