diff --git a/Dockerfile b/Dockerfile
index f2f96d3..bf516d0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -39,6 +39,7 @@ RUN pip install --no-cache-dir --prefix=/install ./evalscope
 
 # ✅ 加这一段
 RUN pip install --no-cache-dir --prefix=/install nltk && \
+    PYTHONPATH=/install/lib/python3.10/site-packages \
     python3 -m nltk.downloader -d /nltk_data punkt
 
 # 拷贝入口文件