The invention belongs to the field of medicine and particularly relates to a method for preparing a solifenacin intermediate. After 2-halogenated diphenyl ketone is used for carbonyl protection, n-butyllithium is used for removing bromine, then the formyl group is added; a condensation reaction with nitromethane and catalytic hydrogenation for reduction are carried out, and then acidification is conducted; later, cyclization is carried out, and a solifenacin intermediate compound I is obtained through alkaline hydrolysis after reduction and chiral resolution. The structural formula of the solifenacin intermediate is shown in the description. According to the method for preparing the solifenacin intermediate, the initial raw materials easy to obtain are utilized, and the production cost is reduced. The process route is advanced, the reaction conditions are mild, the reaction yield is high, less three wastes are caused, expensive and toxic reagents do not exist, reaction solvents can be used repeatedly after distillation, industrial production is facilitated, and implementation value and social, economic and environmental protection benefits are high.