Ensuring reasonable pantograph dynamic parameters is crucial for maintaining pantograph-catenary (PAC) matching performance and reducing maintenance costs. Initially, a dynamic model of PAC, accounting for the rolling motion of the collector head, was established, which is utilised to calculate the contact force of the PAC, acceleration of the collector head, and contact force distribution coefficient along the strip. Additionally, the objective function of optimization is established. Subsequently, the sensitivity of pantograph parameters is investigated using the modified Morris approach, and three optimal parameters are selected in accordance with engineering practice. Finally, the pantograph parameters are optimized by using the PAC dynamic model combined with a genetic algorithm. The results demonstrate that the equivalent mass of the collector head and lower frame are the most sensitive, and the optimization processes significantly improve the dynamic interaction quality of PAC.