Return air inlet filter with sterilization function

The utility model discloses a return air inlet filter with a sterilization function, which belongs to the technical field of return air inlet filters and comprises a return air inlet filter body, a fixing structure, an adjusting structure and a sterilization structure are arranged on the return air inlet filter body, and the fixing structure comprises a limiting plate. A plurality of limiting plates are fixedly connected to the return air inlet filter body, the same fixing block is slidably connected to the corresponding limiting plates, and an adjusting rod is rotatably connected to the fixing block; by arranging the fixing structures and the adjusting structures, due to the fact that the thread directions of the outer walls of two threaded rods are opposite, the two threaded rods can automatically move away from each other in a threaded barrel, and the threaded rods push two corresponding fixing blocks to move away from each other through two corresponding adjusting rods; and after the four fixing blocks ar