Sewage pretreatment device

The utility model relates to the technical field of sewage pretreatment, in particular to a sewage pretreatment device which comprises a treatment tank and a filter cartridge, and the filter cartridge is arranged at the top of the treatment tank to filter impurities in sewage; the top of the treatment tank is connected with a motor through a support, and the output end of the motor is coaxially connected with a stirring assembly extending to the treatment tank. The stirring assembly is coaxially connected with a driving bevel gear which is meshed with the driven bevel gear. The water inlet is forked, impurities are filtered through the filter plate and the filter cartridge, the filter plate is arranged at the forked part of the water inlet and can be prevented from being blocked under the impact of sewage injection, the rotatably arranged filter cartridge filters sewage and turns the impurities to fall off, the blockage of the filter cartridge is also avoided, and the filtered impurities automatically fall of