diff --git a/x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/ClusterDeprecationChecks.java b/x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/ClusterDeprecationChecks.java
index 1d3d25b8828a5..5794549d95ae0 100644
--- a/x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/ClusterDeprecationChecks.java
+++ b/x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/ClusterDeprecationChecks.java
@@ -12,6 +12,8 @@
 import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.metadata.MappingMetadata;
 import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.collect.ImmutableOpenMap;
+import org.elasticsearch.common.compress.CompressedXContent;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.xcontent.XContentHelper;
 import org.elasticsearch.index.IndexSettings;
@@ -167,4 +169,24 @@ static DeprecationIssue checkPollIntervalTooLow(ClusterState state) {
         }
         return null;
     }
+
+    static DeprecationIssue checkTemplatesWithMultipleTypes(ClusterState state) {
+        Set<String> templatesWithMultipleTypes = new HashSet<>();
+        state.getMetadata().getTemplates().forEach((templateCursor) -> {
+            String templateName = templateCursor.key;
+            ImmutableOpenMap<String, CompressedXContent> mappings = templateCursor.value.mappings();
+            if (mappings != null && mappings.size() > 1) {
+                templatesWithMultipleTypes.add(templateName);
+            }
+        });
+        if (templatesWithMultipleTypes.isEmpty()) {
+            return null;
+        }
+        return new DeprecationIssue(DeprecationIssue.Level.CRITICAL,
+            "Some index templates contain multiple mapping types",
+            "https://www.elastic.co/guide/en/elasticsearch/reference/master/removal-of-types.html",
+            "Index templates " + templatesWithMultipleTypes
+            + " define multiple types and so will cause errors when used in index creation"
+            );
+    }
 }
diff --git a/x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/DeprecationChecks.java b/x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/DeprecationChecks.java
index 3f8593b0343c3..c1926827156ff 100644
--- a/x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/DeprecationChecks.java
+++ b/x-pack/plugin/deprecation/src/main/java/org/elasticsearch/xpack/deprecation/DeprecationChecks.java
@@ -38,7 +38,8 @@ private DeprecationChecks() {
             ClusterDeprecationChecks::checkUserAgentPipelines,
             ClusterDeprecationChecks::checkTemplatesWithTooManyFields,
             ClusterDeprecationChecks::checkPollIntervalTooLow,
-            ClusterDeprecationChecks::checkTemplatesWithFieldNamesDisabled
+            ClusterDeprecationChecks::checkTemplatesWithFieldNamesDisabled,
+            ClusterDeprecationChecks::checkTemplatesWithMultipleTypes
         ));
 
 
diff --git a/x-pack/plugin/deprecation/src/test/java/org/elasticsearch/xpack/deprecation/ClusterDeprecationChecksTests.java b/x-pack/plugin/deprecation/src/test/java/org/elasticsearch/xpack/deprecation/ClusterDeprecationChecksTests.java
index 96d3164ecef9f..f32c3acd4cdd0 100644
--- a/x-pack/plugin/deprecation/src/test/java/org/elasticsearch/xpack/deprecation/ClusterDeprecationChecksTests.java
+++ b/x-pack/plugin/deprecation/src/test/java/org/elasticsearch/xpack/deprecation/ClusterDeprecationChecksTests.java
@@ -13,6 +13,7 @@
 import org.elasticsearch.cluster.metadata.Metadata;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.bytes.BytesArray;
+import org.elasticsearch.common.collect.ImmutableOpenMap;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentType;
@@ -21,7 +22,6 @@
 import org.elasticsearch.ingest.IngestService;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.xpack.core.deprecation.DeprecationIssue;
-import org.hamcrest.Matchers;
 
 import java.io.IOException;
 import java.util.Collections;
@@ -32,6 +32,8 @@
 import static org.elasticsearch.xpack.core.ilm.LifecycleSettings.LIFECYCLE_POLL_INTERVAL_SETTING;
 import static org.elasticsearch.xpack.deprecation.DeprecationChecks.CLUSTER_SETTINGS_CHECKS;
 import static org.elasticsearch.xpack.deprecation.IndexDeprecationChecksTests.addRandomFields;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.hasSize;
 
 public class ClusterDeprecationChecksTests extends ESTestCase {
 
@@ -272,7 +274,41 @@ public void testPollIntervalTooLow() {
                 .metadata(okMetadata)
                 .build();
             List<DeprecationIssue> noIssues = DeprecationChecks.filterChecks(CLUSTER_SETTINGS_CHECKS, c -> c.apply(okState));
-            assertThat(noIssues, Matchers.hasSize(0));
+            assertThat(noIssues, hasSize(0));
         }
     }
+
+    public void testIndexTemplatesWithMultipleTypes() throws IOException {
+
+        IndexTemplateMetadata multipleTypes = IndexTemplateMetadata.builder("multiple-types")
+            .patterns(Collections.singletonList("foo"))
+            .putMapping("type1", "{\"type1\":{}}")
+            .putMapping("type2", "{\"type2\":{}}")
+            .build();
+        IndexTemplateMetadata singleType = IndexTemplateMetadata.builder("single-type")
+            .patterns(Collections.singletonList("foo"))
+            .putMapping("type1", "{\"type1\":{}}")
+            .build();
+        ImmutableOpenMap<String, IndexTemplateMetadata> templates = ImmutableOpenMap.<String, IndexTemplateMetadata>builder()
+            .fPut("multiple-types", multipleTypes)
+            .fPut("single-type", singleType)
+            .build();
+        Metadata badMetadata = Metadata.builder()
+            .templates(templates)
+            .build();
+        ClusterState badState = ClusterState.builder(new ClusterName("test")).metadata(badMetadata).build();
+        List<DeprecationIssue> issues = DeprecationChecks.filterChecks(CLUSTER_SETTINGS_CHECKS, c -> c.apply(badState));
+        assertThat(issues, hasSize(1));
+        assertThat(issues.get(0).getDetails(),
+            equalTo("Index templates [multiple-types] define multiple types and so will cause errors when used in index creation"));
+
+        Metadata goodMetadata = Metadata.builder()
+            .templates(ImmutableOpenMap.<String, IndexTemplateMetadata>builder().fPut("single-type", singleType).build())
+            .build();
+        ClusterState goodState = ClusterState.builder(new ClusterName("test")).metadata(goodMetadata).build();
+        assertThat(
+            DeprecationChecks.filterChecks(CLUSTER_SETTINGS_CHECKS, c -> c.apply(goodState)),
+            hasSize(0)
+        );
+    }
 }