Abstract: The electric submersible pumps are the key equipment for exploitation and utilization of oil and gas resources, and it is very important to improve its hydraulic performance and operation stability. Electric submersible pumps are critical equipment in oil and gas field development, and wear-ring clearance is a key parameter affecting their performance and axial force. To investigate the mechanisms underlying the influence of wear-ring clearance on the axial force and performance of electric submersible pumps, this paper utilizes the SST k-ω turbulence model to perform numerical simulations of the three-dimensional flow field within ESPs across various wear-ring clearances. The variations of the axial force and performance were analyzed, and the key flow parameters such as pressure, velocity and vortex structure were compared. The results indicate that as the clearance leakage increases, flow field stability decreases, leading to slight reductions in head and efficiency. Furthermore, variations in the wear-ring clearance exert a notable influence on the axial force of the electric submersible pump. Specifically, under rated flow conditions, a 50% reduction in the front wear-ring clearance leads to a decrease in axial force by approximately 32.33%, while a similar reduction in the rear wear-ring clearance results in a decline in axial force by approximately 63.69%.