diff --git a/src/openlifu/db/database.py b/src/openlifu/db/database.py
index f82dfa48..a747c1a5 100644
--- a/src/openlifu/db/database.py
+++ b/src/openlifu/db/database.py
@@ -414,11 +414,17 @@ def write_volume(self, subject_id, volume_id, volume_name, volume_data_filepath,
 
         try:
             volume_ids = self.get_volume_ids(subject_id)
+            old_volume_data_filepath = None
             if volume_id in volume_ids:
                 if on_conflict == OnConflictOpts.ERROR:
                     raise ValueError(f"Volume with ID {volume_id} already exists for subject {subject_id}.")
                 elif on_conflict == OnConflictOpts.OVERWRITE:
                     self.logger.info(f"Overwriting volume with ID {volume_id} for subject {subject_id}.")
+                    volume_metadata_filepath = self.get_volume_metadata_filepath(subject_id, volume_id)
+                    if volume_metadata_filepath.exists():
+                        with open(volume_metadata_filepath) as file:
+                            old_volume_metadata = json.load(file)
+                        old_volume_data_filepath = volume_metadata_filepath.parent / old_volume_metadata["data_filename"]
                 elif on_conflict == OnConflictOpts.SKIP:
                     self.logger.info(f"Skipping volume with ID {volume_id} for subject {subject_id} as it already exists.")
                     return
@@ -435,6 +441,14 @@ def write_volume(self, subject_id, volume_id, volume_name, volume_data_filepath,
                 file.write(volume_metadata_json)
             shutil.copy(Path(volume_data_filepath), Path(volume_metadata_filepath).parent)
 
+            new_volume_data_filepath = Path(volume_metadata_filepath).parent / Path(volume_data_filepath).name
+            if (
+                old_volume_data_filepath is not None
+                and old_volume_data_filepath != new_volume_data_filepath
+                and old_volume_data_filepath.exists()
+            ):
+                old_volume_data_filepath.unlink()
+
             if volume_id not in volume_ids:
                 volume_ids.append(volume_id)
                 self.write_volume_ids(subject_id, volume_ids)
diff --git a/tests/test_database.py b/tests/test_database.py
index 7530abe7..b070b51b 100644
--- a/tests/test_database.py
+++ b/tests/test_database.py
@@ -581,6 +581,34 @@ def test_write_volume(example_database:Database, tmp_path:Path):
     assert(volume_filepath.name == "example_volume_2.json")
     assert((volume_filepath.parent/"example_volume_2.nii").exists())
 
+def test_issue_136(example_database:Database, tmp_path:Path):
+    subject_id = "example_subject"
+    volume_id = "a_volume_id"
+    volume_name = "a_volume_name"
+    volume_data_path = Path(tmp_path/'test_db_files/a_volume_filename.nii')
+    volume_data_path.parent.mkdir(parents=True, exist_ok=True)
+    volume_data_path.touch()
+    volume_data_path2 = Path(tmp_path/'test_db_files/a_different_volume_filename.nii')
+    volume_data_path2.parent.mkdir(parents=True, exist_ok=True)
+    volume_data_path2.touch()
+
+    # write volume with the data path volume_data_path
+    example_database.write_volume(subject_id, volume_id, volume_name, volume_data_path)
+
+    # check that the file is there in the DB with the expected name
+    volume_filepath = example_database.get_volume_metadata_filepath(subject_id, volume_id)
+    assert((volume_filepath.parent/volume_data_path.name).exists())
+
+    # now overwrite using a different volume data path volume_data_path2, with a different filename
+    example_database.write_volume(subject_id, volume_id, volume_name, volume_data_path2, on_conflict=OnConflictOpts.OVERWRITE)
+
+    # check that the file is there in the DB with the expected name
+    volume_filepath = example_database.get_volume_metadata_filepath(subject_id, volume_id)
+    assert((volume_filepath.parent/volume_data_path2.name).exists())
+
+    # check that the old file was removed
+    assert(not (volume_filepath.parent/volume_data_path.name).exists())
+
 def test_load_solution(example_database:Database, example_session:Session):
     with pytest.raises(FileNotFoundError,match="Solution file not found"):
         example_database.load_solution(example_session, "bogus_solution_id")