Abstract: In order to meet the design requirements of variable speed transmission, on the basis of studying the non-circular pitch curve of Pascal spiral, the mathematical model of high-order modified Pascal spiral non-circular gear pitch curve and its concave-convex discrimination formula were established by introducing high-order and modified principles. In order to analyze that transmission characteristics of high-order modify Pascal spiral non-circular gear, a visual design analysis platform was compiled by using MATLAB, and the factors affect the shape and transmission characteristics of high-order modified Pascal spiral non-circular gear were analyzed by using the design software, which provided a convenient design platform for the subsequent design and application of high-order modified Pascal spiral non-circular gear. The advantages and feasibility of Pascal non-circular gear were verified by comparing with the slider-crank press.