diff --git a/anomalib/pre_processing/transforms/custom.py b/anomalib/pre_processing/transforms/custom.py
index 1f99a19a19..6ca4a67d34 100644
--- a/anomalib/pre_processing/transforms/custom.py
+++ b/anomalib/pre_processing/transforms/custom.py
@@ -3,6 +3,7 @@
 # Copyright (C) 2022 Intel Corporation
 # SPDX-License-Identifier: Apache-2.0
 
+import warnings
 from typing import List, Optional, Tuple
 
 import numpy as np
@@ -19,6 +20,7 @@ def __init__(self, mean: Optional[List[float]] = None, std: Optional[List[float]
             mean: Mean
             std: Standard deviation.
         """
+        warnings.warn("Denormalize is no longer used and will be deprecated in v0.4.0")
         # If no mean and std provided, assign ImageNet values.
         if mean is None:
             mean = [0.485, 0.456, 0.406]