Disclosed are a laser range finding sensor and a range finding method therefor. The laser range finding sensor comprises a motor (120), a control box (130), and a coded disc (150). Under a drive of the motor, the control box rotates relative to the coded disc. The coded disc comprises a plurality of range finding teeth (151). The control box comprises a range finding unit (142), a detection portion (144), and a control unit (140). The detection portion comprises a light transmitter (1440) and a light receiver (1441) disposed opposite to each other. The control box rotates relative to the coded disc, so that the range finding teeth pass between respective positions of the light transmitter and the light receiver. The control box rotates under the drive of the motor for scanning and distance measuring and records a measured distance value in the control unit. The control unit automatically calculates a corresponding local rotation speed when the coded disc rotates by a set angle. The control unit is connected to a rotation speed feedback and adjustment unit configured to adjust the rotation speed of the motor so that the control box is rotated at a constant speed. The laser range finding sensor has a simple structure, needs a low cost, and has a high sensitivity.