diff --git a/rules/dhcprelay.dep b/rules/dhcprelay.dep
index 5f6d77a84f..552fda2480 100644
--- a/rules/dhcprelay.dep
+++ b/rules/dhcprelay.dep
@@ -2,7 +2,7 @@
 SPATH       := $($(SONIC_DHCPRELAY)_SRC_PATH)
 DEP_FILES   := $(SONIC_COMMON_FILES_LIST) rules/dhcprelay.mk rules/dhcprelay.dep   
 DEP_FILES   += $(SONIC_COMMON_BASE_FILES_LIST)
-SMDEP_FILES := $(addprefix $(SPATH)/,$(shell cd $(SPATH) && git ls-files))
+SMDEP_FILES := $(addprefix $(SPATH)/,$(shell cd $(SPATH) && git ls-files --recurse-submodules))
 
 $(SONIC_DHCPRELAY)_CACHE_MODE  := GIT_CONTENT_SHA 
 $(SONIC_DHCPRELAY)_DEP_FLAGS   := $(SONIC_COMMON_FLAGS_LIST)