diff --git a/src/TensorFlowNET.Core/APIs/tf.ops.cs b/src/TensorFlowNET.Core/APIs/tf.ops.cs
index d2ab44b2..cd7a3642 100644
--- a/src/TensorFlowNET.Core/APIs/tf.ops.cs
+++ b/src/TensorFlowNET.Core/APIs/tf.ops.cs
@@ -29,6 +29,9 @@ namespace Tensorflow
         public Tensor assign(Tensor @ref, object value, bool validate_shape = true, bool use_locking = true, string name = null) 
             => state_ops.assign(@ref, value, validate_shape, use_locking, name);
 
+        public Tensor assign(RefVariable @ref, object value, bool validate_shape = true, bool use_locking = true, string name = null)
+            => state_ops.assign(@ref, value, validate_shape, use_locking, name);
+
         public void device(string device_name)
             => get_default_graph().device(device_name);
 
diff --git a/test/TensorFlowNET.UnitTest/Basics/AssignTests.cs b/test/TensorFlowNET.UnitTest/Basics/AssignTests.cs
index 6c593929..0b09f783 100644
--- a/test/TensorFlowNET.UnitTest/Basics/AssignTests.cs
+++ b/test/TensorFlowNET.UnitTest/Basics/AssignTests.cs
@@ -33,5 +33,22 @@ namespace TensorFlowNET.UnitTest.Basics
                 }
             }
         }
+
+        [TestMethod]
+        public void Bug397()
+        {
+            // fix bug https://github.com/SciSharp/TensorFlow.NET/issues/397
+            var W = tf.Variable(-1, name: "weight_" + 1, dtype: tf.float32);
+            var init = tf.global_variables_initializer();
+            var reluEval = tf.nn.relu(W);
+            var nonZero = tf.assign(W, reluEval);
+
+            using (var sess = tf.Session())
+            {
+                sess.run(init);
+                float result = nonZero.eval();
+                Assert.IsTrue(result == 0f);
+            }
+        }
     }
 }
\ No newline at end of file