diff --git a/read_gzp.py b/read_gzp.py
index 4506890..ef1f409 100644
--- a/read_gzp.py
+++ b/read_gzp.py
@@ -32,7 +32,7 @@ def main():
         files = os.listdir(gzp_file)
         for file in files:
             if file.endswith(".gzp"):
-                extract_gzp(file, extensions, output_dir)
+                extract_gzp(os.path.join(gzp_file, file), extensions, output_dir)
     else:
         extract_gzp(gzp_file, extensions, output_dir)