diff --git a/moto/kms/models.py b/moto/kms/models.py
index b4eeb638d..7ea40d8b4 100644
--- a/moto/kms/models.py
+++ b/moto/kms/models.py
@@ -346,7 +346,8 @@ class KmsBackend(BaseBackend):
 
         return plaintext, ciphertext_blob, arn
 
-    def list_resource_tags(self, key_id):
+    def list_resource_tags(self, key_id_or_arn):
+        key_id = self.get_key_id(key_id_or_arn)
         if key_id in self.keys:
             return self.tagger.list_tags_for_resource(key_id)
         raise JsonRESTError(
@@ -354,7 +355,8 @@ class KmsBackend(BaseBackend):
             "The request was rejected because the specified entity or resource could not be found.",
         )
 
-    def tag_resource(self, key_id, tags):
+    def tag_resource(self, key_id_or_arn, tags):
+        key_id = self.get_key_id(key_id_or_arn)
         if key_id in self.keys:
             self.tagger.tag_resource(key_id, tags)
             return {}
@@ -363,7 +365,8 @@ class KmsBackend(BaseBackend):
             "The request was rejected because the specified entity or resource could not be found.",
         )
 
-    def untag_resource(self, key_id, tag_names):
+    def untag_resource(self, key_id_or_arn, tag_names):
+        key_id = self.get_key_id(key_id_or_arn)
         if key_id in self.keys:
             self.tagger.untag_resource_using_names(key_id, tag_names)
             return {}
diff --git a/tests/test_kms/test_kms.py b/tests/test_kms/test_kms.py
index ba4ef1707..2e0af4c5a 100644
--- a/tests/test_kms/test_kms.py
+++ b/tests/test_kms/test_kms.py
@@ -671,6 +671,18 @@ def test__assert_default_policy():
 sort = lambda l: sorted(l, key=lambda d: d.keys())
 
 
+def _check_tags(key_id, created_tags, client):
+    result = client.list_resource_tags(KeyId=key_id)
+    actual = result.get("Tags", [])
+    assert sort(created_tags) == sort(actual)
+
+    client.untag_resource(KeyId=key_id, TagKeys=["key1"])
+
+    actual = client.list_resource_tags(KeyId=key_id).get("Tags", [])
+    expected = [{"TagKey": "key2", "TagValue": "value2"}]
+    assert sort(expected) == sort(actual)
+
+
 @mock_kms
 def test_key_tag_on_create_key_happy():
     client = boto3.client("kms", region_name="us-east-1")
@@ -680,17 +692,19 @@ def test_key_tag_on_create_key_happy():
         {"TagKey": "key2", "TagValue": "value2"},
     ]
     key = client.create_key(Description="test-key-tagging", Tags=tags)
-    key_id = key["KeyMetadata"]["KeyId"]
+    _check_tags(key["KeyMetadata"]["KeyId"], tags, client)
 
-    result = client.list_resource_tags(KeyId=key_id)
-    actual = result.get("Tags", [])
-    assert sort(tags) == sort(actual)
 
-    client.untag_resource(KeyId=key_id, TagKeys=["key1"])
+@mock_kms
+def test_key_tag_on_create_key_on_arn_happy():
+    client = boto3.client("kms", region_name="us-east-1")
 
-    actual = client.list_resource_tags(KeyId=key_id).get("Tags", [])
-    expected = [{"TagKey": "key2", "TagValue": "value2"}]
-    assert sort(expected) == sort(actual)
+    tags = [
+        {"TagKey": "key1", "TagValue": "value1"},
+        {"TagKey": "key2", "TagValue": "value2"},
+    ]
+    key = client.create_key(Description="test-key-tagging", Tags=tags)
+    _check_tags(key["KeyMetadata"]["Arn"], tags, client)
 
 
 @mock_kms
@@ -704,16 +718,21 @@ def test_key_tag_added_happy():
         {"TagKey": "key2", "TagValue": "value2"},
     ]
     client.tag_resource(KeyId=key_id, Tags=tags)
+    _check_tags(key_id, tags, client)
 
-    result = client.list_resource_tags(KeyId=key_id)
-    actual = result.get("Tags", [])
-    assert sort(tags) == sort(actual)
 
-    client.untag_resource(KeyId=key_id, TagKeys=["key1"])
+@mock_kms
+def test_key_tag_added_arn_based_happy():
+    client = boto3.client("kms", region_name="us-east-1")
 
-    actual = client.list_resource_tags(KeyId=key_id).get("Tags", [])
-    expected = [{"TagKey": "key2", "TagValue": "value2"}]
-    assert sort(expected) == sort(actual)
+    key = client.create_key(Description="test-key-tagging")
+    key_id = key["KeyMetadata"]["Arn"]
+    tags = [
+        {"TagKey": "key1", "TagValue": "value1"},
+        {"TagKey": "key2", "TagValue": "value2"},
+    ]
+    client.tag_resource(KeyId=key_id, Tags=tags)
+    _check_tags(key_id, tags, client)
 
 
 @mock_kms_deprecated
diff --git a/tests/test_kms/test_kms_boto3.py b/tests/test_kms/test_kms_boto3.py
index 8b29ad748..34d0a6a4d 100644
--- a/tests/test_kms/test_kms_boto3.py
+++ b/tests/test_kms/test_kms_boto3.py
@@ -398,6 +398,20 @@ def test_list_resource_tags():
     assert response["Tags"][0]["TagValue"] == "string"
 
 
+@mock_kms
+def test_list_resource_tags_with_arn():
+    client = boto3.client("kms", region_name="us-east-1")
+    key = client.create_key(Description="cancel-key-deletion")
+    client.schedule_key_deletion(KeyId=key["KeyMetadata"]["KeyId"])
+
+    keyid = key["KeyMetadata"]["Arn"]
+    client.tag_resource(KeyId=keyid, Tags=[{"TagKey": "string", "TagValue": "string"}])
+
+    response = client.list_resource_tags(KeyId=keyid)
+    assert response["Tags"][0]["TagKey"] == "string"
+    assert response["Tags"][0]["TagValue"] == "string"
+
+
 @pytest.mark.parametrize(
     "kwargs,expected_key_length",
     (