The uniformity of the wake on the submarine propeller disk is the key factor affecting the vibration and noise performance of the propeller. To study the influence of the fillets on the uniformity of submarine wake field and propeller unsteady bearing force, the submarine resistance calculation and self-propulsion calculation were carried out using the Detached-Eddy Simulation (DES) method. The characteristics of the wake field and hydrodynamic performance of the original and improved plan were compared and analyzed in detail. The fillets improve the wake distribution at the propeller disk by reducing the horseshoe vortex, and the fillets mainly affect the flow field characteristics of the inner radius area. The fillets can effectively reduce the axial velocity pulsation and improve the quality of the wake field. The frequency–domain curve shows that the bearing force and torque pulsation value of the improved plan are smaller than that in the original one, indicating that the fillets are conducive to controlling the vibration and noise performance of the submarine propeller. The results show that the fillets can effectively improve the flow field quality in the wake fields and reduce the propeller unsteady bearing force.