Abstract: The precision ball screw is the key functional component of machine tools. The wear between the ball and the raceway is inevitable during service, which degrades the performance and precision of the ball screw. Raceway profile parameters play a critical role in the contact and wear behavior of the ball screw, largely determining the overall performance of the ball screw. This study focuses on a novel ball screw with a second-order osculating raceway profile. The comparative analysis of the wear performance between the second-order osculating raceway and the traditional gothic arch raceway was conducted through the finite element (FE) wear simulation and experiments based on the single-ball-to-straight-raceway equivalent model. Results show that the second-order osculating raceway exhibits a more uniform contact stress distribution and a more even wear pattern. The maximum wear depth of the osculating raceway is approximately 40% lower than that of the gothic arch raceway, but the wear area is larger. Its wear morphology is characterized as "wide and shallow". In addition, the effects of the normal load and the rotational speed on wear depth and volume were quantitatively analyzed. This study provides insights and methods for wear research of the ball screw with a novel raceway profile and for the optimal design of the ball screw.