diff --git a/targets/TARGET_STM/TARGET_STM32L0/flash_api.c b/targets/TARGET_STM/TARGET_STM32L0/flash_api.c
index 77c1fde307..2b954656ed 100644
--- a/targets/TARGET_STM/TARGET_STM32L0/flash_api.c
+++ b/targets/TARGET_STM/TARGET_STM32L0/flash_api.c
@@ -178,7 +178,7 @@ uint8_t flash_get_erase_value(const flash_t *obj)
 {
     (void)obj;
 
-    return 0xFF;
+    return 0x0;
 }
 
 #endif
diff --git a/targets/TARGET_STM/TARGET_STM32L1/flash_api.c b/targets/TARGET_STM/TARGET_STM32L1/flash_api.c
index f6d64ba319..678cc43ea1 100644
--- a/targets/TARGET_STM/TARGET_STM32L1/flash_api.c
+++ b/targets/TARGET_STM/TARGET_STM32L1/flash_api.c
@@ -175,7 +175,7 @@ uint8_t flash_get_erase_value(const flash_t *obj)
 {
     (void)obj;
 
-    return 0xFF;
+    return 0x0;
 }
 
 #endif