diff --git a/src/Microsoft.ML.OnnxTransformer/OnnxSequenceType.cs b/src/Microsoft.ML.OnnxTransformer/OnnxSequenceType.cs
index c8b310b45c..1c2d5a77d8 100644
--- a/src/Microsoft.ML.OnnxTransformer/OnnxSequenceType.cs
+++ b/src/Microsoft.ML.OnnxTransformer/OnnxSequenceType.cs
@@ -56,9 +56,10 @@ public sealed class OnnxSequenceTypeAttribute : DataViewTypeAttribute
     {
         private Type _elemType;
 
-        /// <summary>
-        /// Create a sequence type.
-        /// </summary>
+        // Make default constructor obsolete.
+        // Use default constructor will left the _elemType field empty and cause exception in methods using _elemType.
+        // User will receive compile error when try to use [OnnxSequenceType] attribute directly without specify sequence type
+        [Obsolete("Please specify sequence type when use OnnxSequenceType Attribute", true)]
         public OnnxSequenceTypeAttribute()
         {
         }
diff --git a/test/Microsoft.ML.Tests/OnnxSequenceTypeWithAttributesTest.cs b/test/Microsoft.ML.Tests/OnnxSequenceTypeWithAttributesTest.cs
index e8090aef81..11849c3372 100644
--- a/test/Microsoft.ML.Tests/OnnxSequenceTypeWithAttributesTest.cs
+++ b/test/Microsoft.ML.Tests/OnnxSequenceTypeWithAttributesTest.cs
@@ -65,4 +65,4 @@ public void OnnxSequenceTypeWithColumnNameAttributeTest()
 
         }
     }
-}
+}
\ No newline at end of file