diff --git a/flint-core/src/main/resources/async-query-scheduler-index-mapping.json b/flint-core/src/main/resources/async-query-scheduler-index-mapping.json
new file mode 100644
index 000000000..6beee6f84
--- /dev/null
+++ b/flint-core/src/main/resources/async-query-scheduler-index-mapping.json
@@ -0,0 +1,60 @@
+{
+  "dynamic": false,
+  "properties": {
+    "accountId": {
+      "type": "keyword"
+    },
+    "jobId": {
+      "type": "keyword"
+    },
+    "dataSource": {
+      "type": "keyword"
+    },
+    "scheduledQuery": {
+      "type": "text"
+    },
+    "queryLang": {
+      "type": "keyword"
+    },
+    "lastUpdateTime": {
+      "type": "date",
+      "format": "epoch_millis"
+    },
+    "enabledTime": {
+      "type": "date",
+      "format": "epoch_millis"
+    },
+    "schedule": {
+      "properties": {
+        "initialDelay": {
+          "type": "long"
+        },
+        "interval": {
+          "properties": {
+            "start_time": {
+              "type": "date",
+              "format": "strict_date_time||epoch_millis"
+            },
+            "period": {
+              "type": "integer"
+            },
+            "unit": {
+              "type": "keyword"
+            }
+          }
+        }
+      }
+    },
+    "enabled": {
+      "type": "boolean"
+    },
+    "lockDurationSeconds": {
+      "type": "long",
+      "null_value": -1
+    },
+    "jitter": {
+      "type": "double",
+      "null_value": 0.0
+    }
+  }
+}
\ No newline at end of file
diff --git a/flint-core/src/main/resources/async-query-scheduler-index-mapping.yml b/flint-core/src/main/resources/async-query-scheduler-index-mapping.yml
deleted file mode 100644
index 1aa90e8ed..000000000
--- a/flint-core/src/main/resources/async-query-scheduler-index-mapping.yml
+++ /dev/null
@@ -1,47 +0,0 @@
----
-##
-# Copyright OpenSearch Contributors
-# SPDX-License-Identifier: Apache-2.0
-##
-
-# Schema file for the .async-query-scheduler index
-# Also "dynamic" is set to "false" so that other fields cannot be added.
-dynamic: false
-properties:
-  accountId:
-    type: keyword
-  jobId:
-    type: keyword
-  dataSource:
-    type: keyword
-  scheduledQuery:
-    type: text
-  queryLang:
-    type: keyword
-  lastUpdateTime:
-    type: date
-    format: epoch_millis
-  enabledTime:
-    type: date
-    format: epoch_millis
-  schedule:
-    properties:
-      initialDelay:
-        type: long
-      interval:
-        properties:
-          start_time:
-            type: date
-            format: "strict_date_time||epoch_millis"
-          period:
-            type: integer
-          unit:
-            type: keyword
-  enabled:
-    type: boolean
-  lockDurationSeconds:
-    type: long
-    null_value: -1
-  jitter:
-    type: double
-    null_value: 0.0
\ No newline at end of file
diff --git a/flint-core/src/main/resources/async-query-scheduler-index-settings.json b/flint-core/src/main/resources/async-query-scheduler-index-settings.json
new file mode 100644
index 000000000..7041e27b8
--- /dev/null
+++ b/flint-core/src/main/resources/async-query-scheduler-index-settings.json
@@ -0,0 +1,7 @@
+{
+  "index": {
+    "number_of_shards": "1",
+    "auto_expand_replicas": "0-2",
+    "number_of_replicas": "0"
+  }
+}
\ No newline at end of file
diff --git a/flint-core/src/main/resources/async-query-scheduler-index-settings.yml b/flint-core/src/main/resources/async-query-scheduler-index-settings.yml
deleted file mode 100644
index 386f1f4f3..000000000
--- a/flint-core/src/main/resources/async-query-scheduler-index-settings.yml
+++ /dev/null
@@ -1,11 +0,0 @@
----
-##
-# Copyright OpenSearch Contributors
-# SPDX-License-Identifier: Apache-2.0
-##
-
-# Settings file for the .async-query-scheduler index
-index:
-  number_of_shards: "1"
-  auto_expand_replicas: "0-2"
-  number_of_replicas: "0"
\ No newline at end of file
diff --git a/flint-spark-integration/src/main/scala/org/opensearch/flint/spark/scheduler/OpenSearchAsyncQueryScheduler.java b/flint-spark-integration/src/main/scala/org/opensearch/flint/spark/scheduler/OpenSearchAsyncQueryScheduler.java
index 19532254b..42fcdea40 100644
--- a/flint-spark-integration/src/main/scala/org/opensearch/flint/spark/scheduler/OpenSearchAsyncQueryScheduler.java
+++ b/flint-spark-integration/src/main/scala/org/opensearch/flint/spark/scheduler/OpenSearchAsyncQueryScheduler.java
@@ -48,8 +48,8 @@
  */
 public class OpenSearchAsyncQueryScheduler implements AsyncQueryScheduler {
     public static final String SCHEDULER_INDEX_NAME = ".async-query-scheduler";
-    private static final String SCHEDULER_INDEX_MAPPING_FILE_NAME = "async-query-scheduler-index-mapping.yml";
-    private static final String SCHEDULER_INDEX_SETTINGS_FILE_NAME = "async-query-scheduler-index-settings.yml";
+    private static final String SCHEDULER_INDEX_MAPPING_FILE_NAME = "async-query-scheduler-index-mapping.json";
+    private static final String SCHEDULER_INDEX_SETTINGS_FILE_NAME = "async-query-scheduler-index-settings.json";
     private static final Logger LOG = LogManager.getLogger(OpenSearchAsyncQueryScheduler.class);
 
     private static final ObjectMapper mapper = new ObjectMapper();
@@ -110,8 +110,8 @@ void createAsyncQuerySchedulerIndex(IRestHighLevelClient client) {
              InputStream settingsFileStream = getResourceAsStream(SCHEDULER_INDEX_SETTINGS_FILE_NAME)) {
 
             CreateIndexRequest createIndexRequest = new CreateIndexRequest(SCHEDULER_INDEX_NAME)
-                    .mapping(IOUtils.toString(mappingFileStream, StandardCharsets.UTF_8), XContentType.YAML)
-                    .settings(IOUtils.toString(settingsFileStream, StandardCharsets.UTF_8), XContentType.YAML);
+                    .mapping(IOUtils.toString(mappingFileStream, StandardCharsets.UTF_8), XContentType.JSON)
+                    .settings(IOUtils.toString(settingsFileStream, StandardCharsets.UTF_8), XContentType.JSON);
 
             CreateIndexResponse createIndexResponse = client.createIndex(createIndexRequest, RequestOptions.DEFAULT);
             if (!createIndexResponse.isAcknowledged()) {