The invention provides a method for solving a plurality of air gap relative permeability and the magnetic field of a stator slotted permanent magnet motor. The method comprises firstly, in consideration of a stator slotted effect, establishing a relationship between the plurality of air gap relative permeability and an air gap magnetic flux density; establishing, by using one tooth pitch of the motor as a model, the Laplace equation of the air gap and a magnetic pole region in a polar coordinate system to obtain the magnetic field general solutions of the air gap and the magnetic pole region;then, setting, by using the mathematical law that the magnetic field near a notch surface and a core tooth sharp corner area is divergent, a boundary conditions in a slot area to solve the radial andtangential components of the plurality of air gap relative permeability; and finally, calculating the slotted air gap flux density of the inner and outer rotor permanent magnet motors when the statoris slotted, and verifying the accuracy of the model by the finite element. The method solves the influence of the cogging effect on the radial and tangential directions of the air gap magnetic field,accurately calculates the cogging effect on the radial and tangential air gap magnetic field distribution of the permanent magnet motor under different pole and groove combinations, and has good simplicity and universality.