diff --git a/src/stepfunctions/steps/sagemaker.py b/src/stepfunctions/steps/sagemaker.py
index dba0b64..051a05a 100644
--- a/src/stepfunctions/steps/sagemaker.py
+++ b/src/stepfunctions/steps/sagemaker.py
@@ -115,7 +115,7 @@ class TransformStep(Task):
     Creates a Task State to execute a `SageMaker Transform Job <https://docs.aws.amazon.com/sagemaker/latest/dg/API_CreateTransformJob.html>`_.
     """
 
-    def __init__(self, state_id, transformer, job_name, model_name, data, data_type='S3Prefix', content_type=None, compression_type=None, split_type=None, experiment_config=None, wait_for_completion=True, tags=None, **kwargs):
+    def __init__(self, state_id, transformer, job_name, model_name, data, data_type='S3Prefix', content_type=None, compression_type=None, split_type=None, experiment_config=None, wait_for_completion=True, tags=None, input_filter=None, output_filter=None, join_source=None, **kwargs):
         """
         Args:
             state_id (str): State name whose length **must be** less than or equal to 128 unicode characters. State names **must be** unique within the scope of the whole state machine.
@@ -150,7 +150,10 @@ def __init__(self, state_id, transformer, job_name, model_name, data, data_type=
                 content_type=content_type,
                 compression_type=compression_type,
                 split_type=split_type,
-                job_name=job_name
+                job_name=job_name,
+                input_filter=input_filter,
+                join_source=join_source,
+                output_filter=output_filter
             )
         else:
             parameters = transform_config(
@@ -159,7 +162,10 @@ def __init__(self, state_id, transformer, job_name, model_name, data, data_type=
                 data_type=data_type,
                 content_type=content_type,
                 compression_type=compression_type,
-                split_type=split_type
+                split_type=split_type,
+                input_filter=input_filter,
+                join_source=join_source,
+                output_filter=output_filter
             )
 
         if isinstance(job_name, (ExecutionInput, StepInput)):
@@ -253,7 +259,7 @@ def __init__(self, state_id, endpoint_config_name, model_name, initial_instance_
 
         if isinstance(data_capture_config, DataCaptureConfig):
             parameters['DataCaptureConfig'] = data_capture_config._to_request_dict()
-            
+
         if tags:
             parameters['Tags'] = tags_dict_to_kv_list(tags)
 
diff --git a/tests/unit/test_sagemaker_steps.py b/tests/unit/test_sagemaker_steps.py
index c7ca95e..099a1be 100644
--- a/tests/unit/test_sagemaker_steps.py
+++ b/tests/unit/test_sagemaker_steps.py
@@ -422,6 +422,57 @@ def test_transform_step_creation(pca_transformer):
         'End': True
     }
 
+    step_with_optional_fields = TransformStep('Inference',
+        transformer=pca_transformer,
+        data='s3://sagemaker/inference',
+        job_name='transform-job',
+        model_name='pca-model',
+        experiment_config={
+            'ExperimentName': 'pca_experiment',
+            'TrialName': 'pca_trial',
+            'TrialComponentDisplayName': 'Transform'
+        },
+        tags=DEFAULT_TAGS,
+        join_source='Input',
+        output_filter='$[2:]',
+        input_filter='$[1:]'
+    )
+    assert step_with_optional_fields.to_dict() == {
+        'Type': 'Task',
+        'Parameters': {
+            'ModelName': 'pca-model',
+            'TransformInput': {
+                'DataSource': {
+                    'S3DataSource': {
+                        'S3DataType': 'S3Prefix',
+                        'S3Uri': 's3://sagemaker/inference'
+                    }
+                }
+            },
+            'TransformOutput': {
+                'S3OutputPath': 's3://sagemaker/transform-output'
+            },
+            'TransformJobName': 'transform-job',
+            'TransformResources': {
+                'InstanceCount': 1,
+                'InstanceType': 'ml.c4.xlarge'
+            },
+            'DataProcessing': {
+                'InputFilter': '$[1:]',
+                'OutputFilter': '$[2:]',
+                'JoinSource': 'Input',
+            },
+            'ExperimentConfig': {
+                'ExperimentName': 'pca_experiment',
+                'TrialName': 'pca_trial',
+                'TrialComponentDisplayName': 'Transform'
+            },
+            'Tags': DEFAULT_TAGS_LIST
+        },
+        'Resource': 'arn:aws:states:::sagemaker:createTransformJob.sync',
+        'End': True
+    }
+
 @patch('botocore.client.BaseClient._make_api_call', new=mock_boto_api_call)
 def test_get_expected_model(pca_estimator):
     training_step = TrainingStep('Training', estimator=pca_estimator, job_name='TrainingJob')