diff --git a/moto/iam/models.py b/moto/iam/models.py
index 92ac19da7..8937d262d 100644
--- a/moto/iam/models.py
+++ b/moto/iam/models.py
@@ -213,7 +213,7 @@ class InstanceProfile(BaseModel):
     def get_cfn_attribute(self, attribute_name):
         from moto.cloudformation.exceptions import UnformattedGetAttTemplateException
         if attribute_name == 'Arn':
-            raise NotImplementedError('"Fn::GetAtt" : [ "{0}" , "Arn" ]"')
+            return self.arn
         raise UnformattedGetAttTemplateException()