The invention discloses a manufacturing method of sleeve openings of slip-vent western-style clothes. According to the technical scheme, the manufacturing method comprises the following steps of 1, turning over ends of sleeve sheets to form welts, ironing the welts to form welt folding lines, fixedly sewing sleeve opening linings with the sleeve sheets to make the sleeve opening linings and the sleeve sheets sleeved with each other and leveled, and sewing folding edges formed in the middles of the sleeve sheets with the sleeve opening linings; 2, crocheting large sleeve vents according to thelineation of the sleeve openings, and aligning the sleeve opening linings and the sleeve sheets at the large sleeve vents to be sewed and then ironed and shaped; 3, making coils at the backs of outervents; 4, fixing buttons according to the position of the coils, so that the effect that the sleeve opening linings of the manufactured western-style clothes are prevented from sliding relative to thesleeve sheets is achieved.