diff --git a/moto/dynamodbstreams/models.py b/moto/dynamodbstreams/models.py
index dc6f0e0d3..f62c49877 100644
--- a/moto/dynamodbstreams/models.py
+++ b/moto/dynamodbstreams/models.py
@@ -7,7 +7,7 @@ import base64
 from boto3 import Session
 
 from moto.core import BaseBackend, BaseModel
-from moto.dynamodb2.models import dynamodb_backends
+from moto.dynamodb2.models import dynamodb_backends, DynamoJsonEncoder
 
 
 class ShardIterator(BaseModel):
@@ -137,7 +137,7 @@ class DynamoDBStreamsBackend(BaseBackend):
 
     def get_records(self, iterator_arn, limit):
         shard_iterator = self.shard_iterators[iterator_arn]
-        return json.dumps(shard_iterator.get(limit))
+        return json.dumps(shard_iterator.get(limit), cls=DynamoJsonEncoder)
 
 
 dynamodbstreams_backends = {}
diff --git a/tests/test_dynamodbstreams/test_dynamodbstreams.py b/tests/test_dynamodbstreams/test_dynamodbstreams.py
index 8fad0ff23..065d7280e 100644
--- a/tests/test_dynamodbstreams/test_dynamodbstreams.py
+++ b/tests/test_dynamodbstreams/test_dynamodbstreams.py
@@ -134,6 +134,7 @@ class TestCore:
                 "id": {"S": "entry1"},
                 "first_col": {"S": "bar"},
                 "second_col": {"S": "baz"},
+                "a": {"L": [{"M": {"b": {"S": "bar1"}}}]},
             },
         )
         conn.delete_item(TableName="test-streams", Key={"id": {"S": "entry1"}})