diff --git a/hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSource.java b/hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSource.java
index 120e4655eeda..a53899c476fa 100644
--- a/hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSource.java
+++ b/hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSource.java
@@ -238,6 +238,10 @@ public interface MetricsRegionServerSource extends BaseSource, JvmPauseMonitorSo
   String MAX_COMPACTED_STORE_FILE_REF_COUNT = "maxCompactedStoreFileRefCount";
   String MEMSTORE_SIZE = "memStoreSize";
   String MEMSTORE_SIZE_DESC = "Size of the memstore";
+  String MEMSTORE_HEAP_SIZE = "memStoreHeapSize";
+  String MEMSTORE_HEAP_SIZE_DESC = "On-heap Size of the memstore";
+  String MEMSTORE_OFFHEAP_SIZE = "memStoreOffHeapSize";
+  String MEMSTORE_OFFHEAP_SIZE_DESC = "Off-heap Size of the memstore";
   String STOREFILE_SIZE = "storeFileSize";
   String STOREFILE_SIZE_GROWTH_RATE = "storeFileSizeGrowthRate";
   String MAX_STORE_FILE_AGE = "maxStoreFileAge";
diff --git a/hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSourceImpl.java b/hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSourceImpl.java
index ee5ce34f6b60..bfac0843e331 100644
--- a/hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSourceImpl.java
+++ b/hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSourceImpl.java
@@ -520,6 +520,10 @@ private MetricsRecordBuilder addGaugesToMetricsRecordBuilder(MetricsRecordBuilde
       .addGauge(Interns.info(MAX_STOREFILE_COUNT, MAX_STOREFILE_COUNT_DESC),
         rsWrap.getMaxStoreFiles())
       .addGauge(Interns.info(MEMSTORE_SIZE, MEMSTORE_SIZE_DESC), rsWrap.getMemStoreSize())
+      .addGauge(Interns.info(MEMSTORE_HEAP_SIZE, MEMSTORE_HEAP_SIZE_DESC),
+        rsWrap.getOnHeapMemStoreSize())
+      .addGauge(Interns.info(MEMSTORE_OFFHEAP_SIZE, MEMSTORE_OFFHEAP_SIZE_DESC),
+        rsWrap.getOffHeapMemStoreSize())
       .addGauge(Interns.info(STOREFILE_SIZE, STOREFILE_SIZE_DESC), rsWrap.getStoreFileSize())
       .addGauge(Interns.info(STOREFILE_SIZE_GROWTH_RATE, STOREFILE_SIZE_GROWTH_RATE_DESC),
         rsWrap.getStoreFileSizeGrowthRate())
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMetricsRegionServer.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMetricsRegionServer.java
index 49ce16c87f98..e1cc080f753d 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMetricsRegionServer.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestMetricsRegionServer.java
@@ -83,6 +83,8 @@ public void testWrapperSource() {
     HELPER.assertGauge("hlogFileSize", 1024000, serverSource);
     HELPER.assertGauge("storeFileCount", 300, serverSource);
     HELPER.assertGauge("memstoreSize", 1025, serverSource);
+    HELPER.assertGauge("memstoreHeapSize", 500, serverSource);
+    HELPER.assertGauge("memstoreOffHeapSize", 600, serverSource);
     HELPER.assertGauge("storeFileSize", 1900, serverSource);
     HELPER.assertGauge("storeFileSizeGrowthRate", 50.0, serverSource);
     HELPER.assertCounter("totalRequestCount", 899, serverSource);