diff --git a/metagpt/rag/benchmark/base.py b/metagpt/rag/benchmark/base.py
index 2634f139f..1d8d9c600 100644
--- a/metagpt/rag/benchmark/base.py
+++ b/metagpt/rag/benchmark/base.py
@@ -2,6 +2,7 @@ import asyncio
 import json
 import os
 from typing import List
+from pathlib import Path
 
 import evaluate
 import jieba
@@ -159,16 +160,16 @@ class RAGBenchmark:
 
     @staticmethod
     def load_dataset(ds_names: list[str] = ["all"]):
-        infos =  read_json_file(os.path.join(EXAMPLE_BENCHMARK_PATH, "dataset_info.json"))
+        infos =  read_json_file(Path(EXAMPLE_BENCHMARK_PATH) / "dataset_info.json")
         dataset_config = DatasetConfig(
             datasets=[
                 DatasetInfo(
                     name=name,
                     document_files=[
-                        os.path.join(EXAMPLE_BENCHMARK_PATH, name, file)
+                        Path(EXAMPLE_BENCHMARK_PATH) / name / file,
                         for file in info["document_file"]
                     ],
-                    gt_info=read_json_file(os.path.join(EXAMPLE_BENCHMARK_PATH, name, info["gt_file"])),
+                    gt_info=read_json_file(Path(EXAMPLE_BENCHMARK_PATH) / name / info["gt_file"]),
                 )
                 for dataset_info in infos
                 for name, info in dataset_info.items()