diff --git a/README.md b/README.md
index 0d0d9b7..e1d6166 100644
--- a/README.md
+++ b/README.md
@@ -7,3 +7,4 @@
 [第6回の課題](../../pages/kadaib2.html)
 [Bの第２回の課題](../../pages/kadaib2-1.html)
 [Bの三回目の課題](../../pages/kadaib3.html)
+[Bの4回目の課題](../../pages/kadaib4.html)