The invention discloses a mosquito repellent device for a cowshed. The mosquito repellent device comprises a fixed plate, wherein a protective frame is arranged at the edges of the top part of the fixed plate; the top part of the protective frame is fixedly connected with a first lifting rope; a second lifting rope is fixedly connected with and arranged in the interior of the protective frame; thebottom part of the second lifting rope is fixedly connected with a mosquito attracting bag; the top part of the fixed plate is provided with an ultraviolet lamp; the top part of the fixed plate is provided with a guiding hole; the bottom end of the guiding hole is connected with a funnel; the side walls of the funnel are respectively provided with a mounting hole; an electric net is arranged in mounting holes; a rib is arranged in the electric net; the bottom end of the funnel is connected with a threaded pipe; the edge of the bottom part of the fixed plate is provided with an air suction hood; the bottom part of the air suction hood is provided with a through hole; the threaded pipe is located in the through hole; and the bottom end of the threaded pipe is in sleeve connection with a capthrough a screw thread. The mosquito repellent device provided by the invention can quickly and efficiently repel mosquitoes in the cowshed, has good effects, is free of any toxicity, and is safe andreliable to use.