diff --git a/modelcenter/PP-HelixFold/introduction_en.ipynb b/modelcenter/PP-HelixFold/introduction_en.ipynb
index 450548c825fe223649e841f9499d7d616eee5ea0..b63f5cf03bb1a3520fbb67c9a8a788819d9f329f 100644
--- a/modelcenter/PP-HelixFold/introduction_en.ipynb
+++ b/modelcenter/PP-HelixFold/introduction_en.ipynb
@@ -198,7 +198,7 @@
     "}\n",
     "```\n",
     "\n",
-    "## 6. Copyright\n",
+    "## 7. Copyright\n",
     "\n",
     "PP-HelixFold code is licensed under the Apache 2.0 License, which is same as AlphaFold. However, we use the AlphaFold parameters pretrained by DeepMind, which are made available for non-commercial use only under the terms of the CC BY-NC 4.0 license.\n"
    ]