In　this　study,　the　influence　of　rock　fracture　on　the　swelling　behavior　of　compacted　bentonite　was　investigated　experimentally　with　bentonite　compacted　inside　a　hollow　cylinder　of　fractured　Beishan　granite　from　China.　During　the　test,　hydration　was　allowed　by　letting　water　flowing　into　the　compacted　bentonite　from　the　base　plate,　and　air　being　expelled　from　the　top　plate.　Along　the　sample,　swelling　pressure　and　relative　humidity　were　monitored　at　different　positions.　Results　showed　that　the　presence　of　rock　fracture　significantly　changed　the　hydration　process　of　compacted　bentonite.　The　evolutions　of　swelling　pressure　were　directly　related　to　the　relative　position　to　the　rock　fracture.　At　the　same　height,　for　the　position　closer　to　the　rock　fracture,　a　larger　decrease　in　local　dry　density　occurred,　resulting　in　a　larger　loss　in　swelling　pressure.　This　suggests　that　in　field　conditions　of　radioactive　waste　repository　involving　bentonite　and　rock,　local　filling　of　rock　fracture　by　bentonite　may　occur,　and　the　resulted　bentonite　swelling　pressure　decrease　must　be　accounted　for　in　the　safety　evaluation　of　the　whole　storage　system.