diff --git a/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_ARM_MICRO/partition_M2351_sub.h b/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_ARM_MICRO/partition_M2351_sub.h
index ffe2057d64..221c09d1c6 100644
--- a/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_ARM_MICRO/partition_M2351_sub.h
+++ b/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_ARM_MICRO/partition_M2351_sub.h
@@ -14,8 +14,8 @@
 /* Secure flash size: 256 KB */
 #define NU_TZ_SECURE_FLASH_SIZE     0x40000
 
-/* Secure SRAM size: 24 KB */
-#define NU_TZ_SECURE_SRAM_SIZE      0x6000
+/* Secure SRAM size: 32 KB */
+#define NU_TZ_SECURE_SRAM_SIZE      0x8000
 
 /* NSC region size: 4 KB */
 #define NU_TZ_NSC_REGION_SIZE       0x1000
diff --git a/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_ARM_STD/partition_M2351_sub.h b/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_ARM_STD/partition_M2351_sub.h
index ffe2057d64..221c09d1c6 100644
--- a/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_ARM_STD/partition_M2351_sub.h
+++ b/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_ARM_STD/partition_M2351_sub.h
@@ -14,8 +14,8 @@
 /* Secure flash size: 256 KB */
 #define NU_TZ_SECURE_FLASH_SIZE     0x40000
 
-/* Secure SRAM size: 24 KB */
-#define NU_TZ_SECURE_SRAM_SIZE      0x6000
+/* Secure SRAM size: 32 KB */
+#define NU_TZ_SECURE_SRAM_SIZE      0x8000
 
 /* NSC region size: 4 KB */
 #define NU_TZ_NSC_REGION_SIZE       0x1000
diff --git a/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_GCC_ARM/partition_M2351_sub.h b/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_GCC_ARM/partition_M2351_sub.h
index ffe2057d64..221c09d1c6 100644
--- a/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_GCC_ARM/partition_M2351_sub.h
+++ b/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_GCC_ARM/partition_M2351_sub.h
@@ -14,8 +14,8 @@
 /* Secure flash size: 256 KB */
 #define NU_TZ_SECURE_FLASH_SIZE     0x40000
 
-/* Secure SRAM size: 24 KB */
-#define NU_TZ_SECURE_SRAM_SIZE      0x6000
+/* Secure SRAM size: 32 KB */
+#define NU_TZ_SECURE_SRAM_SIZE      0x8000
 
 /* NSC region size: 4 KB */
 #define NU_TZ_NSC_REGION_SIZE       0x1000
diff --git a/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_IAR/partition_M2351_sub b/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_IAR/partition_M2351_sub
index 27163b8769..218a73b8ba 100644
--- a/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_IAR/partition_M2351_sub
+++ b/targets/TARGET_NUVOTON/TARGET_M2351/device/TOOLCHAIN_IAR/partition_M2351_sub
@@ -3,8 +3,8 @@
 /* Secure flash size: 256 KB */
 define exported symbol NU_TZ_SECURE_FLASH_SIZE  = 0x40000
 
-/* Secure SRAM size: 24 KB */
-define exported symbol NU_TZ_SECURE_SRAM_SIZE   = 0x6000
+/* Secure SRAM size: 32 KB */
+define exported symbol NU_TZ_SECURE_SRAM_SIZE   = 0x8000
 
 /* NSC region size: 4 KB */
 define exported symbol NU_TZ_NSC_REGION_SIZE    = 0x1000