diff --git a/moto/elbv2/models.py b/moto/elbv2/models.py
index 6bc8f860e..3c6afe7f5 100644
--- a/moto/elbv2/models.py
+++ b/moto/elbv2/models.py
@@ -65,6 +65,7 @@ class FakeTargetGroup(BaseModel):
         self.healthy_threshold_count = healthy_threshold_count
         self.unhealthy_threshold_count = unhealthy_threshold_count
         self.load_balancer_arns = []
+        self.tags = {}
 
         self.attributes = {
             'deregistration_delay.timeout_seconds': 300,
@@ -86,6 +87,11 @@ class FakeTargetGroup(BaseModel):
             if not t:
                 raise InvalidTargetError()
 
+    def add_tag(self, key, value):
+        if len(self.tags) >= 10 and key not in self.tags:
+            raise TooManyTagsError()
+        self.tags[key] = value
+
     def health_for(self, target):
         t = self.targets.get(target['id'])
         if t is None:
diff --git a/moto/elbv2/responses.py b/moto/elbv2/responses.py
index 652ecc566..3e8535187 100644
--- a/moto/elbv2/responses.py
+++ b/moto/elbv2/responses.py
@@ -266,10 +266,17 @@ class ELBV2Response(BaseResponse):
         resource_arns = self._get_multi_param('ResourceArns.member')
 
         for arn in resource_arns:
-            load_balancer = self.elbv2_backend.load_balancers.get(arn)
-            if not load_balancer:
+            if ':targetgroup' in arn:
+                resource = self.elbv2_backend.target_groups.get(arn)
+                if not resource:
+                    raise TargetGroupNotFoundError()
+            elif ':loadbalancer' in arn:
+                resource = self.elbv2_backend.load_balancers.get(arn)
+                if not resource:
+                    raise LoadBalancerNotFoundError()
+            else:
                 raise LoadBalancerNotFoundError()
-            self._add_tags(load_balancer)
+            self._add_tags(resource)
 
         template = self.response_template(ADD_TAGS_TEMPLATE)
         return template.render()
@@ -279,30 +286,41 @@ class ELBV2Response(BaseResponse):
         tag_keys = self._get_multi_param('TagKeys.member')
 
         for arn in resource_arns:
-            load_balancer = self.elbv2_backend.load_balancers.get(arn)
-            if not load_balancer:
+            if ':targetgroup' in arn:
+                resource = self.elbv2_backend.target_groups.get(arn)
+                if not resource:
+                    raise TargetGroupNotFoundError()
+            elif ':loadbalancer' in arn:
+                resource = self.elbv2_backend.load_balancers.get(arn)
+                if not resource:
+                    raise LoadBalancerNotFoundError()
+            else:
                 raise LoadBalancerNotFoundError()
-            [load_balancer.remove_tag(key) for key in tag_keys]
+            [resource.remove_tag(key) for key in tag_keys]
 
         template = self.response_template(REMOVE_TAGS_TEMPLATE)
         return template.render()
 
     def describe_tags(self):
-        elbs = []
-        for key, value in self.querystring.items():
-            if "ResourceArns.member" in key:
-                number = key.split('.')[2]
-                load_balancer_arn = self._get_param(
-                    'ResourceArns.member.{0}'.format(number))
-                elb = self.elbv2_backend.load_balancers.get(load_balancer_arn)
-                if not elb:
+        resource_arns = self._get_multi_param('ResourceArns.member')
+        resources = []
+        for arn in resource_arns:
+            if ':targetgroup' in arn:
+                resource = self.elbv2_backend.target_groups.get(arn)
+                if not resource:
+                    raise TargetGroupNotFoundError()
+            elif ':loadbalancer' in arn:
+                resource = self.elbv2_backend.load_balancers.get(arn)
+                if not resource:
                     raise LoadBalancerNotFoundError()
-                elbs.append(elb)
+            else:
+                raise LoadBalancerNotFoundError()
+            resources.append(resource)
 
         template = self.response_template(DESCRIBE_TAGS_TEMPLATE)
-        return template.render(load_balancers=elbs)
+        return template.render(resources=resources)
 
-    def _add_tags(self, elb):
+    def _add_tags(self, resource):
         tag_values = []
         tag_keys = []
 
@@ -324,7 +342,7 @@ class ELBV2Response(BaseResponse):
             raise DuplicateTagKeysError(counts[0])
 
         for tag_key, tag_value in zip(tag_keys, tag_values):
-            elb.add_tag(tag_key, tag_value)
+            resource.add_tag(tag_key, tag_value)
 
 
 ADD_TAGS_TEMPLATE = """<AddTagsResponse xmlns="http://elasticloadbalancing.amazonaws.com/doc/2015-12-01/">
@@ -344,11 +362,11 @@ REMOVE_TAGS_TEMPLATE = """<RemoveTagsResponse xmlns="http://elasticloadbalancing
 DESCRIBE_TAGS_TEMPLATE = """<DescribeTagsResponse xmlns="http://elasticloadbalancing.amazonaws.com/doc/2015-12-01/">
   <DescribeTagsResult>
     <TagDescriptions>
-      {% for load_balancer in load_balancers %}
+      {% for resource in resources %}
       <member>
-        <ResourceArn>{{ load_balancer.arn }}</ResourceArn>
+        <ResourceArn>{{ resource.arn }}</ResourceArn>
         <Tags>
-          {% for key, value in load_balancer.tags.items() %}
+          {% for key, value in resource.tags.items() %}
           <member>
             <Value>{{ value }}</Value>
             <Key>{{ key }}</Key>
diff --git a/tests/test_elbv2/test_elbv2.py b/tests/test_elbv2/test_elbv2.py
index e84cd0080..21799ddcf 100644
--- a/tests/test_elbv2/test_elbv2.py
+++ b/tests/test_elbv2/test_elbv2.py
@@ -251,6 +251,12 @@ def test_create_target_group_and_listeners():
         UnhealthyThresholdCount=2,
         Matcher={'HttpCode': '200'})
     target_group = response.get('TargetGroups')[0]
+    target_group_arn = target_group['TargetGroupArn']
+
+    # Add tags to the target group
+    conn.add_tags(ResourceArns=[target_group_arn], Tags=[{'Key': 'target', 'Value': 'group'}])
+    conn.describe_tags(ResourceArns=[target_group_arn])['TagDescriptions'][0]['Tags'].should.equal(
+        [{'Key': 'target', 'Value': 'group'}])
 
     # Check it's in the describe_target_groups response
     response = conn.describe_target_groups()