diff --git a/arch/xtensa/include/esp32/memory_layout.h b/arch/xtensa/include/esp32/memory_layout.h
index edd880ba434..729a613eec8 100644
--- a/arch/xtensa/include/esp32/memory_layout.h
+++ b/arch/xtensa/include/esp32/memory_layout.h
@@ -96,3 +96,8 @@
 #  define ESP32_IMEM_START  0x3ffe7e40
 #endif
 
+/* Region of unused ROM App data */
+
+#define HEAP_REGION_ROMAPP_START  0x3ffe4360
+#define HEAP_REGION_ROMAPP_END    0x3ffe5230
+
diff --git a/arch/xtensa/src/esp32/esp32_allocateheap.c b/arch/xtensa/src/esp32/esp32_allocateheap.c
index 866e78eef5b..9b9afa36668 100644
--- a/arch/xtensa/src/esp32/esp32_allocateheap.c
+++ b/arch/xtensa/src/esp32/esp32_allocateheap.c
@@ -96,8 +96,15 @@ void xtensa_add_region(void)
 {
   size_t region2_start = HEAP_REGION2_START + XTENSA_IMEM_REGION_SIZE;
 
+#ifndef CONFIG_SMP
   umm_addregion((FAR void *)region2_start,
                 (size_t)(uintptr_t)&_eheap - region2_start);
+#else
+  umm_addregion((FAR void *)region2_start,
+                (size_t)HEAP_REGION2_END - region2_start);
+  umm_addregion((FAR void *)HEAP_REGION3_START,
+                (size_t)&_eheap - HEAP_REGION3_START);
+#endif
 
 #if defined(CONFIG_ESP32_SPIRAM)
   /* Check for any additional memory regions */
diff --git a/boards/xtensa/esp32/esp32-devkitc/configs/smp/defconfig b/boards/xtensa/esp32/esp32-devkitc/configs/smp/defconfig
index 23eafc67acd..deb67a2a9f3 100644
--- a/boards/xtensa/esp32/esp32-devkitc/configs/smp/defconfig
+++ b/boards/xtensa/esp32/esp32-devkitc/configs/smp/defconfig
@@ -28,7 +28,7 @@ CONFIG_HAVE_CXXINITIALIZE=y
 CONFIG_IDLETHREAD_STACKSIZE=3072
 CONFIG_INTELHEX_BINARY=y
 CONFIG_MAX_TASKS=16
-CONFIG_MM_REGIONS=2
+CONFIG_MM_REGIONS=3
 CONFIG_NFILE_DESCRIPTORS=8
 CONFIG_NSH_ARCHINIT=y
 CONFIG_NSH_BUILTIN_APPS=y
diff --git a/boards/xtensa/esp32/esp32-devkitc/configs/wapi_smp/defconfig b/boards/xtensa/esp32/esp32-devkitc/configs/wapi_smp/defconfig
index 27c5f353a35..f40ca647b26 100644
--- a/boards/xtensa/esp32/esp32-devkitc/configs/wapi_smp/defconfig
+++ b/boards/xtensa/esp32/esp32-devkitc/configs/wapi_smp/defconfig
@@ -41,7 +41,7 @@ CONFIG_HAVE_CXXINITIALIZE=y
 CONFIG_IDLETHREAD_STACKSIZE=2048
 CONFIG_INTELHEX_BINARY=y
 CONFIG_IOB_NBUFFERS=128
-CONFIG_MM_REGIONS=2
+CONFIG_MM_REGIONS=3
 CONFIG_NAME_MAX=48
 CONFIG_NETDB_DNSCLIENT=y
 CONFIG_NETDEVICES=y
diff --git a/boards/xtensa/esp32/esp32-devkitc/src/esp32_boot.c b/boards/xtensa/esp32/esp32-devkitc/src/esp32_boot.c
index b3c6f7397c9..740c89c9fbf 100644
--- a/boards/xtensa/esp32/esp32-devkitc/src/esp32_boot.c
+++ b/boards/xtensa/esp32/esp32-devkitc/src/esp32_boot.c
@@ -27,7 +27,9 @@
 #include <debug.h>
 
 #include <nuttx/board.h>
+#include <nuttx/mm/mm.h>
 #include <arch/board/board.h>
+#include <arch/esp32/memory_layout.h>
 
 #include "esp32-devkitc.h"
 
@@ -78,5 +80,17 @@ void board_late_initialize(void)
   /* Perform board-specific initialization */
 
   esp32_bringup();
+
+#ifdef CONFIG_SMP
+  /* To avoid corrupting the heap, this region of memory (~3KB) is not
+   * included until the APP CPU has started.
+   * So we can't add it with the rest of the regions at xtensa_add_region(),
+   * that function is called early from up_initialize().  We wait until the
+   * SMP bringup is complete.
+   */
+
+  umm_addregion((FAR void *)HEAP_REGION_ROMAPP_START,
+                (size_t)(HEAP_REGION_ROMAPP_END - HEAP_REGION_ROMAPP_START));
+#endif
 }
 #endif
diff --git a/boards/xtensa/esp32/esp32-ethernet-kit/src/esp32_boot.c b/boards/xtensa/esp32/esp32-ethernet-kit/src/esp32_boot.c
index cf964c3a2ae..e173894e03f 100644
--- a/boards/xtensa/esp32/esp32-ethernet-kit/src/esp32_boot.c
+++ b/boards/xtensa/esp32/esp32-ethernet-kit/src/esp32_boot.c
@@ -27,7 +27,9 @@
 #include <debug.h>
 
 #include <nuttx/board.h>
+#include <nuttx/mm/mm.h>
 #include <arch/board/board.h>
+#include <arch/esp32/memory_layout.h>
 
 #include "esp32-ethernet-kit.h"
 
@@ -78,5 +80,17 @@ void board_late_initialize(void)
   /* Perform board-specific initialization */
 
   esp32_bringup();
+
+#ifdef CONFIG_SMP
+  /* To avoid corrupting the heap, this region of memory (~3KB) is not
+   * included until the APP CPU has started.
+   * So we can't add it with the rest of the regions at xtensa_add_region(),
+   * that function is called early from up_initialize().  We wait until the
+   * SMP bringup is complete.
+   */
+
+  umm_addregion((FAR void *)HEAP_REGION_ROMAPP_START,
+                (size_t)(HEAP_REGION_ROMAPP_END - HEAP_REGION_ROMAPP_START));
+#endif
 }
 #endif
diff --git a/boards/xtensa/esp32/esp32-wrover-kit/src/esp32_boot.c b/boards/xtensa/esp32/esp32-wrover-kit/src/esp32_boot.c
index bf05463e85b..25f7de63a21 100644
--- a/boards/xtensa/esp32/esp32-wrover-kit/src/esp32_boot.c
+++ b/boards/xtensa/esp32/esp32-wrover-kit/src/esp32_boot.c
@@ -27,7 +27,9 @@
 #include <debug.h>
 
 #include <nuttx/board.h>
+#include <nuttx/mm/mm.h>
 #include <arch/board/board.h>
+#include <arch/esp32/memory_layout.h>
 
 #include "esp32-wrover-kit.h"
 
@@ -83,5 +85,17 @@ void board_late_initialize(void)
   /* Perform board-specific initialization */
 
   esp32_bringup();
+
+#ifdef CONFIG_SMP
+  /* To avoid corrupting the heap, this region of memory (~3KB) is not
+   * included until the APP CPU has started.
+   * So we can't add it with the rest of the regions at xtensa_add_region(),
+   * that function is called early from up_initialize().  We wait until the
+   * SMP bringup is complete.
+   */
+
+  umm_addregion((FAR void *)HEAP_REGION_ROMAPP_START,
+                (size_t)(HEAP_REGION_ROMAPP_END - HEAP_REGION_ROMAPP_START));
+#endif
 }
 #endif