diff --git a/perception/traffic_light_classifier/README.md b/perception/traffic_light_classifier/README.md
index 6b07c73e93b3d..ed3bfb9a040b6 100644
--- a/perception/traffic_light_classifier/README.md
+++ b/perception/traffic_light_classifier/README.md
@@ -8,7 +8,8 @@ traffic_light_classifier is a package for classifying traffic light labels using
 
 ### cnn_classifier
 
-Traffic light labels are classified by MobileNetV2.
+Traffic light labels are classified by MobileNetV2.  
+Totally 37600 (26300 for training, 6800 for evaluation and 4500 for test) TIER IV internal images of Japanese traffic lights were used for fine-tuning.
 
 ### hsv_classifier