PURPOSE: A removal device for attached creatures of an underwater anti-pollution net is provided to prevent a filtering net from being clogged up by attached creatures by removing creatures attached to the filtering net using a tidal difference, to prevent pollution in the water and to reduce inconvenience on underwater works and an economical loss. CONSTITUTION: The removal device for attached creatures of an underwater anti-pollution net comprises the steps of sinking a filtering net(20) provided with a buoy(10) in the water, connecting an anchor(30) fixed to the vertical bottom by connecting from the lower part of the filtering net with a connecting rope(40) to install the filtering net downward vertically, equipping connecting ropes(40a)(40b) for preventing the movement of the filtering net by a tidal difference under the water by connecting anchors(30a)(30b) fixed to both sides of the bottom, and equipping a removal part of attached creatures(50) located to both sides of the filtering net(20) by self-buoyancy at the state of connecting each lower end with connecting ropes(40c)(40d) connected to the anchor(30) fixed to the straight lower bottom of the filtering net, moved by a tidal difference of seawater and crashed into the filtering net(20) to drop attached creatures from the filtering net.