In order to study the influence of the weight distribution function on lens design, on the basis of constructing the minimization model, the spline interpolation method was used to process the weight function of the transition region, and three groups of weight distribution functions were designed to connect the high weight region and the low weight region. According to different weight distribution functions, the corresponding progressive addition lens was designed, and the simulation, machining and evaluation were carried out. The experimental results showed that the weight distribution matrix has an impact on the optical performance of the lens. The faster the weight changes in the transition region of the average curvature and the difference between the principal curvature of the surface, the better the optical performance of the lens. Therefore, using the weight function with fast change of transition region is beneficial to reduce the astigmatism around the lens and optimize the lens power and astigmatism distribution.