diff --git a/CHANGELOG.md b/CHANGELOG.md
index a1c8f296dcff0..c09bbac169a14 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -57,6 +57,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Added equals/hashcode for named DocValueFormat.DateTime inner class ([#6357](https://github.com/opensearch-project/OpenSearch/pull/6357))
 - Fixed bug for searchable snapshot to take 'base_path' of blob into account ([#6558](https://github.com/opensearch-project/OpenSearch/pull/6558))
 - Fix fuzziness validation ([#5805](https://github.com/opensearch-project/OpenSearch/pull/5805))
+- Avoid negative memory result in IndicesQueryCache stats calculation ([#6917](https://github.com/opensearch-project/OpenSearch/pull/6917))
 - Fix GetSnapshots to not return non-existent snapshots with ignore_unavailable=true ([#6839](https://github.com/opensearch-project/OpenSearch/pull/6839))
 
 ### Security
diff --git a/server/src/main/java/org/opensearch/indices/IndicesQueryCache.java b/server/src/main/java/org/opensearch/indices/IndicesQueryCache.java
index 78970267f67c2..2669da3f417c3 100644
--- a/server/src/main/java/org/opensearch/indices/IndicesQueryCache.java
+++ b/server/src/main/java/org/opensearch/indices/IndicesQueryCache.java
@@ -128,13 +128,17 @@ public QueryCacheStats getStats(ShardId shard) {
 
         // We also have some shared ram usage that we try to distribute to
         // proportionally to their number of cache entries of each shard
-        long totalSize = 0;
-        for (QueryCacheStats s : stats.values()) {
-            totalSize += s.getCacheSize();
+        if (stats.isEmpty()) {
+            shardStats.add(new QueryCacheStats(sharedRamBytesUsed, 0, 0, 0, 0));
+        } else {
+            long totalSize = 0;
+            for (QueryCacheStats s : stats.values()) {
+                totalSize += s.getCacheSize();
+            }
+            final double weight = totalSize == 0 ? 1d / stats.size() : ((double) shardStats.getCacheSize()) / totalSize;
+            final long additionalRamBytesUsed = Math.round(weight * sharedRamBytesUsed);
+            shardStats.add(new QueryCacheStats(additionalRamBytesUsed, 0, 0, 0, 0));
         }
-        final double weight = totalSize == 0 ? 1d / stats.size() : ((double) shardStats.getCacheSize()) / totalSize;
-        final long additionalRamBytesUsed = Math.round(weight * sharedRamBytesUsed);
-        shardStats.add(new QueryCacheStats(additionalRamBytesUsed, 0, 0, 0, 0));
         return shardStats;
     }
 
diff --git a/server/src/test/java/org/opensearch/indices/IndicesQueryCacheTests.java b/server/src/test/java/org/opensearch/indices/IndicesQueryCacheTests.java
index 24d8d51042548..4cca989843277 100644
--- a/server/src/test/java/org/opensearch/indices/IndicesQueryCacheTests.java
+++ b/server/src/test/java/org/opensearch/indices/IndicesQueryCacheTests.java
@@ -143,6 +143,7 @@ public void testBasics() throws IOException {
         assertEquals(0L, stats.getCacheCount());
         assertEquals(0L, stats.getHitCount());
         assertEquals(0L, stats.getMissCount());
+        assertEquals(0L, stats.getMemorySizeInBytes());
 
         assertEquals(1, s.count(new DummyQuery(0)));
 
@@ -151,6 +152,7 @@ public void testBasics() throws IOException {
         assertEquals(1L, stats.getCacheCount());
         assertEquals(0L, stats.getHitCount());
         assertEquals(1L, stats.getMissCount());
+        assertTrue(stats.getMemorySizeInBytes() > 0L && stats.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         for (int i = 1; i < 20; ++i) {
             assertEquals(1, s.count(new DummyQuery(i)));
@@ -161,6 +163,7 @@ public void testBasics() throws IOException {
         assertEquals(20L, stats.getCacheCount());
         assertEquals(0L, stats.getHitCount());
         assertEquals(20L, stats.getMissCount());
+        assertTrue(stats.getMemorySizeInBytes() > 0L && stats.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         s.count(new DummyQuery(10));
 
@@ -169,6 +172,7 @@ public void testBasics() throws IOException {
         assertEquals(20L, stats.getCacheCount());
         assertEquals(1L, stats.getHitCount());
         assertEquals(20L, stats.getMissCount());
+        assertTrue(stats.getMemorySizeInBytes() > 0L && stats.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         IOUtils.close(r, dir);
 
@@ -178,6 +182,7 @@ public void testBasics() throws IOException {
         assertEquals(20L, stats.getCacheCount());
         assertEquals(1L, stats.getHitCount());
         assertEquals(20L, stats.getMissCount());
+        assertTrue(stats.getMemorySizeInBytes() > 0L && stats.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         cache.onClose(shard);
 
@@ -187,6 +192,7 @@ public void testBasics() throws IOException {
         assertEquals(0L, stats.getCacheCount());
         assertEquals(0L, stats.getHitCount());
         assertEquals(0L, stats.getMissCount());
+        assertTrue(stats.getMemorySizeInBytes() >= 0L && stats.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         cache.close(); // this triggers some assertions
     }
@@ -227,12 +233,14 @@ public void testTwoShards() throws IOException {
         assertEquals(1L, stats1.getCacheCount());
         assertEquals(0L, stats1.getHitCount());
         assertEquals(1L, stats1.getMissCount());
+        assertTrue(stats1.getMemorySizeInBytes() >= 0L && stats1.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         QueryCacheStats stats2 = cache.getStats(shard2);
         assertEquals(0L, stats2.getCacheSize());
         assertEquals(0L, stats2.getCacheCount());
         assertEquals(0L, stats2.getHitCount());
         assertEquals(0L, stats2.getMissCount());
+        assertTrue(stats2.getMemorySizeInBytes() >= 0L && stats2.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         assertEquals(1, s2.count(new DummyQuery(0)));
 
@@ -241,12 +249,14 @@ public void testTwoShards() throws IOException {
         assertEquals(1L, stats1.getCacheCount());
         assertEquals(0L, stats1.getHitCount());
         assertEquals(1L, stats1.getMissCount());
+        assertTrue(stats1.getMemorySizeInBytes() >= 0L && stats1.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         stats2 = cache.getStats(shard2);
         assertEquals(1L, stats2.getCacheSize());
         assertEquals(1L, stats2.getCacheCount());
         assertEquals(0L, stats2.getHitCount());
         assertEquals(1L, stats2.getMissCount());
+        assertTrue(stats2.getMemorySizeInBytes() >= 0L && stats2.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         for (int i = 0; i < 20; ++i) {
             assertEquals(1, s2.count(new DummyQuery(i)));
@@ -257,12 +267,14 @@ public void testTwoShards() throws IOException {
         assertEquals(1L, stats1.getCacheCount());
         assertEquals(0L, stats1.getHitCount());
         assertEquals(1L, stats1.getMissCount());
+        assertTrue(stats1.getMemorySizeInBytes() >= 0L && stats1.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         stats2 = cache.getStats(shard2);
         assertEquals(10L, stats2.getCacheSize());
         assertEquals(20L, stats2.getCacheCount());
         assertEquals(1L, stats2.getHitCount());
         assertEquals(20L, stats2.getMissCount());
+        assertTrue(stats2.getMemorySizeInBytes() >= 0L && stats2.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         IOUtils.close(r1, dir1);
 
@@ -272,12 +284,14 @@ public void testTwoShards() throws IOException {
         assertEquals(1L, stats1.getCacheCount());
         assertEquals(0L, stats1.getHitCount());
         assertEquals(1L, stats1.getMissCount());
+        assertTrue(stats1.getMemorySizeInBytes() >= 0L && stats1.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         stats2 = cache.getStats(shard2);
         assertEquals(10L, stats2.getCacheSize());
         assertEquals(20L, stats2.getCacheCount());
         assertEquals(1L, stats2.getHitCount());
         assertEquals(20L, stats2.getMissCount());
+        assertTrue(stats2.getMemorySizeInBytes() >= 0L && stats2.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         cache.onClose(shard1);
 
@@ -287,12 +301,14 @@ public void testTwoShards() throws IOException {
         assertEquals(0L, stats1.getCacheCount());
         assertEquals(0L, stats1.getHitCount());
         assertEquals(0L, stats1.getMissCount());
+        assertTrue(stats1.getMemorySizeInBytes() >= 0L && stats1.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         stats2 = cache.getStats(shard2);
         assertEquals(10L, stats2.getCacheSize());
         assertEquals(20L, stats2.getCacheCount());
         assertEquals(1L, stats2.getHitCount());
         assertEquals(20L, stats2.getMissCount());
+        assertTrue(stats2.getMemorySizeInBytes() >= 0L && stats2.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         IOUtils.close(r2, dir2);
         cache.onClose(shard2);
@@ -303,12 +319,14 @@ public void testTwoShards() throws IOException {
         assertEquals(0L, stats1.getCacheCount());
         assertEquals(0L, stats1.getHitCount());
         assertEquals(0L, stats1.getMissCount());
+        assertTrue(stats1.getMemorySizeInBytes() >= 0L && stats1.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         stats2 = cache.getStats(shard2);
         assertEquals(0L, stats2.getCacheSize());
         assertEquals(0L, stats2.getCacheCount());
         assertEquals(0L, stats2.getHitCount());
         assertEquals(0L, stats2.getMissCount());
+        assertTrue(stats2.getMemorySizeInBytes() >= 0L && stats2.getMemorySizeInBytes() < Long.MAX_VALUE);
 
         cache.close(); // this triggers some assertions
     }