diff --git a/elasticsearch/src/main/java/org/apache/calcite/adapter/elasticsearch/ElasticsearchSchemaFactory.java b/elasticsearch/src/main/java/org/apache/calcite/adapter/elasticsearch/ElasticsearchSchemaFactory.java
index b36ca1aa648..aeaec2fa0ff 100644
--- a/elasticsearch/src/main/java/org/apache/calcite/adapter/elasticsearch/ElasticsearchSchemaFactory.java
+++ b/elasticsearch/src/main/java/org/apache/calcite/adapter/elasticsearch/ElasticsearchSchemaFactory.java
@@ -45,6 +45,7 @@
 import java.io.IOException;
 import java.security.KeyManagementException;
 import java.security.NoSuchAlgorithmException;
+import java.util.Comparator;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
@@ -159,6 +160,8 @@ public ElasticsearchSchemaFactory() {
         throw new IllegalArgumentException
         ("Both 'coordinates' and 'hosts' is missing in configuration. Provide one of them.");
       }
+      List<HttpHost> sortedHost = getSortedHost(hosts);
+
       final String pathPrefix = (String) map.get("pathPrefix");
 
       // Enable or Disable SSL Verification
@@ -174,7 +177,7 @@ public ElasticsearchSchemaFactory() {
       String username = (String) map.get("username");
       String password = (String) map.get("password");
       final RestClient client =
-          connect(hosts, pathPrefix, username, password, disableSSLVerification);
+          connect(sortedHost, pathPrefix, username, password, disableSSLVerification);
       final String index = (String) map.get("index");
 
       return new ElasticsearchSchema(client, new ObjectMapper(), index);
@@ -183,6 +186,15 @@ public ElasticsearchSchemaFactory() {
     }
   }
 
+  protected static List<HttpHost> getSortedHost(List<HttpHost> hosts) {
+    List<HttpHost> sortedHosts =
+        hosts
+            .stream()
+            .sorted(Comparator.comparing(HttpHost::toString, String::compareTo))
+            .collect(Collectors.toList());
+    return sortedHosts;
+  }
+
   /**
    * Builds Elastic rest client from user configuration.
    *
diff --git a/elasticsearch/src/test/java/org/apache/calcite/adapter/elasticsearch/ElasticSearchAdapterTest.java b/elasticsearch/src/test/java/org/apache/calcite/adapter/elasticsearch/ElasticSearchAdapterTest.java
index fb18e5b9fa4..578e0e7d634 100644
--- a/elasticsearch/src/test/java/org/apache/calcite/adapter/elasticsearch/ElasticSearchAdapterTest.java
+++ b/elasticsearch/src/test/java/org/apache/calcite/adapter/elasticsearch/ElasticSearchAdapterTest.java
@@ -26,6 +26,8 @@
 import org.apache.calcite.util.Bug;
 import org.apache.calcite.util.TestUtil;
 
+import org.apache.http.HttpHost;
+
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.io.LineProcessor;
@@ -53,6 +55,7 @@
 import java.util.Map;
 import java.util.function.Consumer;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 import static java.util.Objects.requireNonNull;
@@ -771,4 +774,21 @@ private static Consumer<ResultSet> sortedResultSetChecker(String column,
             "state=AR; EXPR$1=3; EXPR$2=3");
   }
 
+  /**
+   * Test case for
+   * <a href="https://issues.apache.org/jira/browse/CALCITE-6725">[CALCITE-6725]
+   * The caching mechanism key in ElasticsearchSchemaFactory is affected by the order of hosts</a>.
+   */
+  @Test void testSortHosts() {
+    HttpHost host1 = HttpHost.create("192.168.1.200:8080");
+    HttpHost host2 = HttpHost.create("192.168.1.100:8080");
+    HttpHost host3 = HttpHost.create("192.168.1.150:8080");
+    List<HttpHost> hosts = Arrays.asList(host1, host2, host3);
+    List<HttpHost> sortedHosts = ElasticsearchSchemaFactory.getSortedHost(hosts);
+    assertEquals(3, sortedHosts.size());
+    assertEquals("http://192.168.1.100:8080", sortedHosts.get(0).toString());
+    assertEquals("http://192.168.1.150:8080", sortedHosts.get(1).toString());
+    assertEquals("http://192.168.1.200:8080", sortedHosts.get(2).toString());
+  }
+
 }