The utility model relates to a tunnel infiltration protection device belongs to tunnel job facilities field, including water drainage tank, joint bar, contact muscle, sealing layer, water drainage tank is unanimous with the shape of tunnel, last even the seting up its fixed required joint bar preformed hole of water drainage tank, pass in every joint bar preformed hole a thong muscle with water drainage tank fixed mounting on the rock -wall of tunnel, the clearance department welding of joint bar and joint bar preformed hole, the contact muscle welds on the joint bar, supports water drainage tank as keel frame, the adoption sealing layer seals between the rock -wall of water drainage tank and tunnel. The utility model discloses a joint bar, the contact muscle with water drainage tank fixedmounting on the rock -wall of tunnel to adopt the sealing layer to seal between the rock -wall of water drainage tank and tunnel, the infiltration trickling on the tunnel is trickled after collecingin the side ditch of branch tunnel both sides on the water drainage tank of iron sheet preparation, to construction branch tunnel, the utility model discloses can replace grouting construction for theconstruction progress reduces the cost, and recycle does.