diff --git a/tensorflow/python/ops/signal/mel_ops.py b/tensorflow/python/ops/signal/mel_ops.py
index cf0bed9ef1b..9b8cbd83064 100644
--- a/tensorflow/python/ops/signal/mel_ops.py
+++ b/tensorflow/python/ops/signal/mel_ops.py
@@ -99,7 +99,7 @@ def linear_to_mel_weight_matrix(num_mel_bins=20,
                                 upper_edge_hertz=3800.0,
                                 dtype=dtypes.float32,
                                 name=None):
-  """Returns a matrix to warp linear scale spectrograms to the [mel scale][mel].
+  r"""Returns a matrix to warp linear scale spectrograms to the [mel scale][mel].
 
   Returns a weight matrix that can be used to re-weight a `Tensor` containing
   `num_spectrogram_bins` linearly sampled frequency information from