diff --git a/server/src/main/java/org/opensearch/action/admin/cluster/health/ClusterHealthResponse.java b/server/src/main/java/org/opensearch/action/admin/cluster/health/ClusterHealthResponse.java
index d9094e307fff1..841231c971eaa 100644
--- a/server/src/main/java/org/opensearch/action/admin/cluster/health/ClusterHealthResponse.java
+++ b/server/src/main/java/org/opensearch/action/admin/cluster/health/ClusterHealthResponse.java
@@ -90,7 +90,7 @@ public class ClusterHealthResponse extends ActionResponse implements StatusToXCo
             // ClusterStateHealth fields
             int numberOfNodes = (int) parsedObjects[i++];
             int numberOfDataNodes = (int) parsedObjects[i++];
-            boolean hasDiscoveredMaster = (boolean) parsedObjects[i++];
+            boolean hasDiscoveredMaster = Boolean.TRUE.equals(parsedObjects[i++]);
             int activeShards = (int) parsedObjects[i++];
             int relocatingShards = (int) parsedObjects[i++];
             int activePrimaryShards = (int) parsedObjects[i++];
@@ -151,7 +151,7 @@ public class ClusterHealthResponse extends ActionResponse implements StatusToXCo
         // ClusterStateHealth fields
         PARSER.declareInt(constructorArg(), new ParseField(NUMBER_OF_NODES));
         PARSER.declareInt(constructorArg(), new ParseField(NUMBER_OF_DATA_NODES));
-        PARSER.declareBoolean(constructorArg(), new ParseField(DISCOVERED_MASTER));
+        PARSER.declareBoolean(optionalConstructorArg(), new ParseField(DISCOVERED_MASTER));
         PARSER.declareInt(constructorArg(), new ParseField(ACTIVE_SHARDS));
         PARSER.declareInt(constructorArg(), new ParseField(RELOCATING_SHARDS));
         PARSER.declareInt(constructorArg(), new ParseField(ACTIVE_PRIMARY_SHARDS));
diff --git a/server/src/test/java/org/opensearch/action/admin/cluster/health/ClusterHealthResponsesTests.java b/server/src/test/java/org/opensearch/action/admin/cluster/health/ClusterHealthResponsesTests.java
index decad9d6f840e..5af15396dbefa 100644
--- a/server/src/test/java/org/opensearch/action/admin/cluster/health/ClusterHealthResponsesTests.java
+++ b/server/src/test/java/org/opensearch/action/admin/cluster/health/ClusterHealthResponsesTests.java
@@ -228,7 +228,7 @@ public void testParseFromXContentWithDiscoveredMasterField() throws IOException
                 NamedXContentRegistry.EMPTY,
                 DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
                 "{\"cluster_name\":\"535799904437:7-1-3-node\",\"status\":\"green\","
-                    + "\"timed_out\":false,\"number_of_nodes\":6,\"number_of_data_nodes\":3,\"discovered_master\":false,"
+                    + "\"timed_out\":false,\"number_of_nodes\":6,\"number_of_data_nodes\":3,\"discovered_master\":true,"
                     + "\"active_primary_shards\":4,\"active_shards\":5,\"relocating_shards\":0,\"initializing_shards\":0,"
                     + "\"unassigned_shards\":0,\"delayed_unassigned_shards\":0,\"number_of_pending_tasks\":0,"
                     + "\"number_of_in_flight_fetch\":0,\"task_max_waiting_in_queue_millis\":0,"
@@ -236,6 +236,27 @@ public void testParseFromXContentWithDiscoveredMasterField() throws IOException
             )
         ) {
 
+            ClusterHealthResponse clusterHealth = ClusterHealthResponse.fromXContent(parser);
+            assertNotNull(clusterHealth);
+            assertThat(clusterHealth.getClusterName(), Matchers.equalTo("535799904437:7-1-3-node"));
+            assertThat(clusterHealth.getNumberOfNodes(), Matchers.equalTo(6));
+            assertThat(clusterHealth.hasDiscoveredMaster(), Matchers.equalTo(true));
+        }
+    }
+
+    public void testParseFromXContentWithoutDiscoveredMasterField() throws IOException {
+        try (
+            XContentParser parser = JsonXContent.jsonXContent.createParser(
+                NamedXContentRegistry.EMPTY,
+                DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
+                "{\"cluster_name\":\"535799904437:7-1-3-node\",\"status\":\"green\","
+                    + "\"timed_out\":false,\"number_of_nodes\":6,\"number_of_data_nodes\":3,"
+                    + "\"active_primary_shards\":4,\"active_shards\":5,\"relocating_shards\":0,\"initializing_shards\":0,"
+                    + "\"unassigned_shards\":0,\"delayed_unassigned_shards\":0,\"number_of_pending_tasks\":0,"
+                    + "\"number_of_in_flight_fetch\":0,\"task_max_waiting_in_queue_millis\":0,"
+                    + "\"active_shards_percent_as_number\":100}"
+            )
+        ) {
             ClusterHealthResponse clusterHealth = ClusterHealthResponse.fromXContent(parser);
             assertNotNull(clusterHealth);
             assertThat(clusterHealth.getClusterName(), Matchers.equalTo("535799904437:7-1-3-node"));