diff --git a/targets/TARGET_NUVOTON/TARGET_M451/device/TOOLCHAIN_GCC_ARM/m451_retarget.c b/targets/TARGET_NUVOTON/TARGET_M451/device/TOOLCHAIN_GCC_ARM/m451_retarget.c
index 470af43..c45bd82 100644
--- a/targets/TARGET_NUVOTON/TARGET_M451/device/TOOLCHAIN_GCC_ARM/m451_retarget.c
+++ b/targets/TARGET_NUVOTON/TARGET_M451/device/TOOLCHAIN_GCC_ARM/m451_retarget.c
@@ -11,10 +11,13 @@
 
 #include "M451Series.h"
 #include <errno.h>
+#include "nu_miscutil.h"
 
 extern uint32_t __mbed_sbrk_start;
 extern uint32_t __mbed_krbs_start;
 
+#define NU_HEAP_ALIGN       32
+
 /**
  * The default implementation of _sbrk() (in common/retarget.cpp) for GCC_ARM requires one-region model (heap and stack share one region), which doesn't
  * fit two-region model (heap and stack are two distinct regions), for example, NUMAKER-PFM-NUC472 locates heap on external SRAM. Define __wrap__sbrk() to
@@ -23,8 +26,8 @@
 void *__wrap__sbrk(int incr)
 {
     static uint32_t heap_ind = (uint32_t) &__mbed_sbrk_start;
-    uint32_t heap_ind_old = heap_ind;
-    uint32_t heap_ind_new = (heap_ind_old + incr + 7) & ~7;
+    uint32_t heap_ind_old = NU_ALIGN_UP(heap_ind, NU_HEAP_ALIGN);
+    uint32_t heap_ind_new = NU_ALIGN_UP(heap_ind_old + incr, NU_HEAP_ALIGN);
     
     if (heap_ind_new > &__mbed_krbs_start) {
         errno = ENOMEM;
diff --git a/targets/TARGET_NUVOTON/TARGET_NUC472/device/TOOLCHAIN_GCC_ARM/nuc472_retarget.c b/targets/TARGET_NUVOTON/TARGET_NUC472/device/TOOLCHAIN_GCC_ARM/nuc472_retarget.c
index d5c3d87..273b3df 100644
--- a/targets/TARGET_NUVOTON/TARGET_NUC472/device/TOOLCHAIN_GCC_ARM/nuc472_retarget.c
+++ b/targets/TARGET_NUVOTON/TARGET_NUC472/device/TOOLCHAIN_GCC_ARM/nuc472_retarget.c
@@ -11,10 +11,13 @@
 
 #include "NUC472_442.h"
 #include <errno.h>
+#include "nu_miscutil.h"
 
 extern uint32_t __mbed_sbrk_start;
 extern uint32_t __mbed_krbs_start;
 
+#define NU_HEAP_ALIGN       32
+
 /**
  * The default implementation of _sbrk() (in common/retarget.cpp) for GCC_ARM requires one-region model (heap and stack share one region), which doesn't
  * fit two-region model (heap and stack are two distinct regions), for example, NUMAKER-PFM-NUC472 locates heap on external SRAM. Define __wrap__sbrk() to
@@ -23,8 +26,8 @@
 void *__wrap__sbrk(int incr)
 {
     static uint32_t heap_ind = (uint32_t) &__mbed_sbrk_start;
-    uint32_t heap_ind_old = heap_ind;
-    uint32_t heap_ind_new = (heap_ind_old + incr + 7) & ~7;
+    uint32_t heap_ind_old = NU_ALIGN_UP(heap_ind, NU_HEAP_ALIGN);
+    uint32_t heap_ind_new = NU_ALIGN_UP(heap_ind_old + incr, NU_HEAP_ALIGN);
     
     if (heap_ind_new > &__mbed_krbs_start) {
         errno = ENOMEM;
diff --git a/targets/TARGET_NUVOTON/nu_miscutil.h b/targets/TARGET_NUVOTON/nu_miscutil.h
index 5d06724..fd1cc9e 100644
--- a/targets/TARGET_NUVOTON/nu_miscutil.h
+++ b/targets/TARGET_NUVOTON/nu_miscutil.h
@@ -24,6 +24,8 @@
 #define NU_MAX(a,b) ((a)>(b)?(a):(b))
 #define NU_MIN(a,b) ((a)<(b)?(a):(b))
 #define NU_CLAMP(x, min, max)   NU_MIN(NU_MAX((x), (min)), (max))
+#define NU_ALIGN_DOWN(X, ALIGN)     ((X) & ~((ALIGN) - 1))
+#define NU_ALIGN_UP(X, ALIGN)       (((X) + (ALIGN) - 1) & ~((ALIGN) - 1))
 
 void nu_nop(uint32_t n);