The invention discloses an angle positioning device and an angle positioning method. The angle positioning device comprises a box body, a middle shaft, an angle wheel, a taper rod and a fixing block,wherein several teeth are distributed on the periphery of the angle wheel, a V-shaped groove is formed between every two teeth, the taper rod is connected to the upper portion of the box body throughthreads, the taper rod is provided with a conical end portion, the conical end portion is matched with the V-shaped grooves, the conical end portion faces the angle wheel, and the axis of the taper rod and the axis of the middle shaft are perpendicular and located in the same plane. According to the angle positioning device and the angle positioning method, the rotating angle of the tool is controlled by limiting rotating and fixing of the angle wheel, so that one-time clamping and multi-angle machining of a machining part are realized, different angle ranges can be realized only by changing the different angle wheels in the using process, and the effects of being economical and practical are achieved.