The invention discloses a bracket for screw rotation and nut movement mounting of an underneath type sink. The bracket comprises a pressing frame, a rack and adjusting devices, wherein the pressing frame is mounted outside the sink from bottom to top in a sleeve manner and propped against lower surfaces of edges of the sink, the rack is mounted on a cabinet, and a plurality of adjusting devices are arranged between the pressing frame and the rack. Each adjusting device comprises an adjusting screw, a moving nut, a fixed nut and two lock nuts, the moving nut and the fixed nut are arranged at two ends of the adjusting screw in a sleeving manner respectively, the adjusting screw is rotated to enable the moving nut and the fixed nut to move oppositely, the two lock nuts are arranged on inner sides of the moving nut and the fixed nut respectively, the screw is arranged at the lower end of the fixed nut and fixed on the rack by a nut, a pressing block is arranged between the upper end of the moving nut and the pressing frame, and the upper end of the moving nut and the lower end surface of the pressing block are in spherical fit. With the adoption of the structure, the bracket is convenient to mount and dismount, firm and reliable.