diff --git a/arch/platform/native/Makefile.native b/arch/platform/native/Makefile.native
index 24f433796..bee104a6c 100644
--- a/arch/platform/native/Makefile.native
+++ b/arch/platform/native/Makefile.native
@@ -30,6 +30,8 @@ CONTIKI_SOURCEFILES += $(CONTIKI_TARGET_SOURCEFILES)
 # Enable nullmac by default
 MAKE_MAC ?= MAKE_MAC_NULLMAC
 
+CLEAN += *.native
+
 ### Define the CPU directory
 CONTIKI_CPU=$(CONTIKI)/arch/cpu/native
 include $(CONTIKI)/arch/cpu/native/Makefile.native
diff --git a/arch/platform/sky/Makefile.sky b/arch/platform/sky/Makefile.sky
index 0398486b0..9467603a4 100644
--- a/arch/platform/sky/Makefile.sky
+++ b/arch/platform/sky/Makefile.sky
@@ -4,6 +4,8 @@ CONTIKI_TARGET_SOURCEFILES += contiki-sky-platform.c \
 	sht11.c sht11-sensor.c light-sensor.c battery-sensor.c \
 	button-sensor.c
 
+CLEAN += *.sky
+
 include $(CONTIKI)/arch/platform/sky/Makefile.common
 
 MODULES += arch/dev/cc2420 arch/dev/sht11 arch/dev/ds2411 os/storage/cfs