The invention relates to a fixture for machining a brake cover of a motorcycle copper/steel fiber non-asbestos drum brake, and is characterized by comprising a frame which consists of a bottom plate, a drill sleeve guide plate and a side plate, wherein a cylinder is fixed on the bottom plate; a top plate provided with a concave hole is fixedly connected to a piston of the cylinder; a first drill sleeve, a second drill sleeve and a third drill sleeve which are opposite to a positioning hole, a central shaft sleeve hole and a cam hole of the brake cover are fixed on the drill sleeve guide plate; the three drill sleeves are step drill sleeves; small-diameter sections of the step drill sleeves are positioned in the drill sleeve guide plate, and ends of the step drill sleeves extend out of thedrill sleeve guide plate; and the distance from the center of the first drill sleeve to the center of the second drill sleeve is equal to the distance from the center of the third drill sleeve to thecenter of the second drill sleeve. The brake cover of the drum brake produced by the fixture has a good brake effect, small brake abnormal sound and low using cost; the brake cover and brake shoes are well matched; and the brake shoes are interchangeable.