In order to improve the energy-absorbing performance of the main energy-absorbing structure at the cab end of the urban rail vehicles, the underframe end sill and the sheet thickness of the main energy-absorbing structure were optimized by means of simulation analysis. Considering the influence of optimal location on energy absorption, the collision model of cab car versus cab car modal of one urban rail vehicle with a relative velocity of 25 km/h was developed. The maximum impact velocity without crushing and the energy absorption before and after structural optimization were obtained by collision analysis and calculation. The results showed that increasing the stiffness of the underframe end sill and reducing the sheet thickness of the main energy-absorbing structure can satisfy the orderly controllable deformation law of the cab end energy-absorbing system, as well as the energy-absorbing performance can be improved, which provided a theoretical reference for the optimization design of the main energy-absorbing structure.