To improve the performance of the direct-drive PMSM with toroidal windings (NTWDDPMSM) after shifting the magnetic poles (SMP), some design parameters such as the pole arc coefficient, permanent magnet magnetization height, air-gap length and slot opening width are selected as optimization variables, and the Taguchi method is adopted to improve torque and reduce torque fluctuations as optimization objectives, increase the efficiency and decrease the total harmonic distortion (THD) of electromotive force (EFM) as constraints. The experimental orthogonal table is established according to the number of the optimization variables and their levels, and finite-element analyses are taken for the orthogonal table. The finite-element results are analyzed, and the best optimization scheme is obtained. Compared with the NTWDDPMSM after SMP, it can be concluded that the torque and efficiency have improved by 10.63% and 1.3%, respectively. Moreover, the torque ripple and the THD of back EMF have reduced by 29.09% and 4.01%.