diff --git a/samcli/local/apigw/local_apigw_service.py b/samcli/local/apigw/local_apigw_service.py
index c18304064a..7cef57d664 100644
--- a/samcli/local/apigw/local_apigw_service.py
+++ b/samcli/local/apigw/local_apigw_service.py
@@ -231,6 +231,7 @@ def _parse_lambda_output(lambda_output, binary_types, flask_request):
         :param str lambda_output: Output from Lambda Invoke
         :return: Tuple(int, dict, str, bool)
         """
+        # pylint: disable-msg=too-many-statements
         json_output = json.loads(lambda_output)
 
         if not isinstance(json_output, dict):
@@ -251,6 +252,14 @@ def _parse_lambda_output(lambda_output, binary_types, flask_request):
             LOG.error(message)
             raise TypeError(message)
 
+        try:
+            if body:
+                body = str(body)
+        except ValueError:
+            message = "Non null response bodies should be able to convert to string: {}".format(body)
+            LOG.error(message)
+            raise TypeError(message)
+
         # API Gateway only accepts statusCode, body, headers, and isBase64Encoded in
         # a response shape.
         invalid_keys = LocalApigwService._invalid_apig_response_keys(json_output)
diff --git a/tests/integration/local/start_api/test_start_api.py b/tests/integration/local/start_api/test_start_api.py
index 84fbf2da79..4d4a7b2a69 100644
--- a/tests/integration/local/start_api/test_start_api.py
+++ b/tests/integration/local/start_api/test_start_api.py
@@ -479,6 +479,12 @@ def test_function_writing_to_stderr(self):
         self.assertEquals(response.status_code, 200)
         self.assertEquals(response.json(), {'hello': 'world'})
 
+    def test_integer_body(self):
+        response = requests.get(self.url + "/echo_integer_body")
+
+        self.assertEquals(response.status_code, 200)
+        self.assertEquals(response.content.decode('utf-8'), '42')
+
 
 class TestServiceRequests(StartApiIntegBaseClass):
     """
diff --git a/tests/integration/testdata/start_api/main.py b/tests/integration/testdata/start_api/main.py
index 7e3875cdfc..fc6bc06482 100644
--- a/tests/integration/testdata/start_api/main.py
+++ b/tests/integration/testdata/start_api/main.py
@@ -4,39 +4,36 @@
 
 
 def handler(event, context):
-
     return {"statusCode": 200, "body": json.dumps({"hello": "world"})}
 
 
 def echo_event_handler(event, context):
-
     return {"statusCode": 200, "body": json.dumps(event)}
 
 
 def echo_event_handler_2(event, context):
-
     event['handler'] = 'echo_event_handler_2'
 
     return {"statusCode": 200, "body": json.dumps(event)}
 
 
-def content_type_setter_handler(event, context):
+def echo_integer_body(event, context):
+    return {"statusCode": 200, "body": 42}
+
 
+def content_type_setter_handler(event, context):
     return {"statusCode": 200, "body": "hello", "headers": {"Content-Type": "text/plain"}}
 
 
 def only_set_status_code_handler(event, context):
-
     return {"statusCode": 200}
 
 
 def only_set_body_handler(event, context):
-
     return {"body": json.dumps({"hello": "world"})}
 
 
 def string_status_code_handler(event, context):
-
     return {"statusCode": "200", "body": json.dumps({"hello": "world"})}
 
 
diff --git a/tests/integration/testdata/start_api/template.yaml b/tests/integration/testdata/start_api/template.yaml
index d9786fb52f..763009613a 100644
--- a/tests/integration/testdata/start_api/template.yaml
+++ b/tests/integration/testdata/start_api/template.yaml
@@ -73,6 +73,19 @@ Resources:
             Method: GET
             Path: /echoeventbody
 
+  EchoIntegerBodyFunction:
+    Type: AWS::Serverless::Function
+    Properties:
+      Handler: main.echo_integer_body
+      Runtime: python3.6
+      CodeUri: .
+      Events:
+        EchoEventBodyPath:
+          Type: Api
+          Properties:
+            Method: GET
+            Path: /echo_integer_body
+
   ContentTypeSetterFunction:
     Type: AWS::Serverless::Function
     Properties: