diff --git a/localstack-core/localstack/services/stepfunctions/asl/component/state/state_execution/state_task/service/state_task_service.py b/localstack-core/localstack/services/stepfunctions/asl/component/state/state_execution/state_task/service/state_task_service.py
index da96e0d6a18a1..eb9680eb3fbb7 100644
--- a/localstack-core/localstack/services/stepfunctions/asl/component/state/state_execution/state_task/service/state_task_service.py
+++ b/localstack-core/localstack/services/stepfunctions/asl/component/state/state_execution/state_task/service/state_task_service.py
@@ -106,8 +106,7 @@ def _to_boto_request_value(self, request_value: Any, value_shape: Shape) -> Any:
         elif isinstance(value_shape, StringShape) and not isinstance(request_value, str):
             boto_request_value = to_json_str(request_value)
         elif value_shape.type_name == "blob" and not isinstance(boto_request_value, bytes):
-            if not isinstance(boto_request_value, str):
-                boto_request_value = to_json_str(request_value, separators=(":", ","))
+            boto_request_value = to_json_str(request_value, separators=(",", ":"))
             boto_request_value = to_bytes(boto_request_value)
         return boto_request_value
 
diff --git a/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py b/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py
index f97031483c683..06770cb988c9d 100644
--- a/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py
+++ b/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py
@@ -8,7 +8,7 @@
     create_and_record_execution,
     create_state_machine_with_iam_role,
 )
-from localstack.utils.strings import short_uid
+from localstack.utils.strings import short_uid, to_str
 from tests.aws.services.stepfunctions.templates.base.base_templates import BaseTemplate as BT
 from tests.aws.services.stepfunctions.templates.services.services_templates import (
     ServicesTemplates as ST,
@@ -310,13 +310,15 @@ def test_s3_put_object(
         sfn_snapshot,
         body,
     ):
+        file_key = f"file-key-{short_uid()}"
         bucket_name = s3_create_bucket()
+        sfn_snapshot.add_transformer(RegexTransformer(file_key, "file-key"))
         sfn_snapshot.add_transformer(RegexTransformer(bucket_name, "bucket-name"))
 
         template = ST.load_sfn_template(ST.AWS_SDK_S3_PUT_OBJECT)
         definition = json.dumps(template)
 
-        exec_input = json.dumps({"Bucket": bucket_name, "Key": "file-key", "Body": body})
+        exec_input = json.dumps({"Bucket": bucket_name, "Key": file_key, "Body": body})
         create_and_record_execution(
             aws_client,
             create_state_machine_iam_role,
@@ -325,3 +327,7 @@ def test_s3_put_object(
             definition,
             exec_input,
         )
+        get_object_response = aws_client.s3.get_object(Bucket=bucket_name, Key=file_key)
+        body = get_object_response["Body"].read()
+        body_str = to_str(body)
+        sfn_snapshot.match("s3-object-content-body", body_str)
diff --git a/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.snapshot.json b/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.snapshot.json
index 3070e6ea06675..580ecca843dba 100644
--- a/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.snapshot.json
+++ b/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.snapshot.json
@@ -2348,7 +2348,7 @@
     }
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[str]": {
-    "recorded-date": "11-06-2024, 07:42:53",
+    "recorded-date": "13-12-2024, 15:20:04",
     "recorded-content": {
       "get_execution_history": {
         "events": [
@@ -2465,11 +2465,12 @@
           "HTTPHeaders": {},
           "HTTPStatusCode": 200
         }
-      }
+      },
+      "s3-object-content-body": "\"text data\""
     }
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[dict]": {
-    "recorded-date": "11-06-2024, 07:43:09",
+    "recorded-date": "13-12-2024, 15:20:52",
     "recorded-content": {
       "get_execution_history": {
         "events": [
@@ -2592,11 +2593,14 @@
           "HTTPHeaders": {},
           "HTTPStatusCode": 200
         }
+      },
+      "s3-object-content-body": {
+        "Dict": "Value"
       }
     }
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[list]": {
-    "recorded-date": "11-06-2024, 07:43:26",
+    "recorded-date": "13-12-2024, 15:21:44",
     "recorded-content": {
       "get_execution_history": {
         "events": [
@@ -2722,11 +2726,12 @@
           "HTTPHeaders": {},
           "HTTPStatusCode": 200
         }
-      }
+      },
+      "s3-object-content-body": "[\"List\",\"Data\"]"
     }
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[bool]": {
-    "recorded-date": "11-06-2024, 07:43:42",
+    "recorded-date": "13-12-2024, 15:22:31",
     "recorded-content": {
       "get_execution_history": {
         "events": [
@@ -2843,11 +2848,12 @@
           "HTTPHeaders": {},
           "HTTPStatusCode": 200
         }
-      }
+      },
+      "s3-object-content-body": "false"
     }
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[num]": {
-    "recorded-date": "11-06-2024, 07:43:58",
+    "recorded-date": "13-12-2024, 15:23:18",
     "recorded-content": {
       "get_execution_history": {
         "events": [
@@ -2964,7 +2970,8 @@
           "HTTPHeaders": {},
           "HTTPStatusCode": 200
         }
-      }
+      },
+      "s3-object-content-body": "0"
     }
   }
 }
diff --git a/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.validation.json b/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.validation.json
index 427c39f0aed2b..a942d43d2cfdc 100644
--- a/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.validation.json
+++ b/tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.validation.json
@@ -27,19 +27,19 @@
     "last_validated_date": "2024-05-23T19:11:47+00:00"
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[bool]": {
-    "last_validated_date": "2024-06-11T07:43:42+00:00"
+    "last_validated_date": "2024-12-13T15:22:31+00:00"
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[dict]": {
-    "last_validated_date": "2024-06-11T07:43:09+00:00"
+    "last_validated_date": "2024-12-13T15:20:52+00:00"
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[list]": {
-    "last_validated_date": "2024-06-11T07:43:26+00:00"
+    "last_validated_date": "2024-12-13T15:21:44+00:00"
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[num]": {
-    "last_validated_date": "2024-06-11T07:43:58+00:00"
+    "last_validated_date": "2024-12-13T15:23:18+00:00"
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_s3_put_object[str]": {
-    "last_validated_date": "2024-06-11T07:42:53+00:00"
+    "last_validated_date": "2024-12-13T15:20:04+00:00"
   },
   "tests/aws/services/stepfunctions/v2/services/test_aws_sdk_task_service.py::TestTaskServiceAwsSdk::test_sfn_send_task_outcome_with_no_such_token[state_machine_template0]": {
     "last_validated_date": "2024-04-10T18:55:26+00:00"