The invention discloses a membrane covering deodorization system which comprises a machine body, a frame structure and a first membrane body, wherein the machine body is of a rectangular sewage tank structure; the frame structure consists of a plurality of fastening steel ropes; the first membrane body is laid above the fastening steel ropes; corners of the first membrane body are fixed on the machine body through anchoring corner steel; and a first overhaul hole is formed above the first membrane body. The membrane covering deodorization system has the benefits of being compact in structure and high in automatic degree; by adopting a horizontally pulled membrane covering mode, a sewage tank is sealed, components H2S and NH3 in odor are respectively neutralized by using a washing tower andare finally filtered by using a microorganism filtering material, then multi-stage filtration treatment is implemented, so that the odor can be comprehensively purified, the odor finally meets emission standards and is discharged out, and the problems that conventional sewage tanks are mostly of opened structures, odor is directly diffused, serious atmosphere pollution can be caused, and meanwhile, the living of people can be seriously affected, can be effectively solved.