The invention relates to a method for preparing spandex fibers with low breaking rate, in particular to a method for manufacturing spandex by introducing a blend solution of an abrasion-resistant agent and a flow promoter into a polyurethane urea spinning solution; the method includes: 1) blending and dissolving the abrasion-resistant agent and the flow promoter in an organic solvent to obtain a blend solution A; 2) adding the blend solution A into the polyurethane urea spinning solution B to prepare a spinning dope C, and performing spinning and winding with the spinning stock solution C. Themethod herein is simple and convenient to implement and can be widely applied to spandex fibers of different varieties, and the breaking condition of the prepared spandex fibers is obviously alleviated.