The invention discloses a permanent magnet motor optimization design method considering disturbance type design variable intervals in the field of motor optimization design. Firstly, design variables of a permanent magnet motor are constructed, corresponding optimization objects, optimization models and constraint conditions are determined, then initial intervals of the design variables are determined, optimal disturbance intervals of the design variables are determined by the aid of the constraint conditions, finally, optimal values of the design variables and optimal values of the optimization objects are obtained through joint simulation of software, and final optimization models are obtained. The method aims to solve the problem of disturbance of the design variable optimization intervals in the determination process and considers the problems of the effect of initial intervals with larger design variables on optimization efficiency and the accuracy of design variable results, through limitation on the constraint conditions, the optimal intervals of the design variables are determined, multiple optimization objects are weighed by the constructed optimization models, so that comprehensive optimal solutions are obtained, the design cycle is shortened, the design cost is reduced, and the method has the advantages of being simple to operate and effective in work.