Studying the biomechanical response of human head in traffic accidents is helpful to the clinical diagnosis and treatment of head injury and the design of pedestrian protection measures. In order to obtain the collision parameters such as landing moment, speed and head angle, the Pc-Crash software is used to accurately reproduce the actual pedestrian-vehicle collision accident. On this basis, the finite element model of pedestrian head is established and the collision parameters are applied as boundary conditions to the head-to-ground collision analysis, and the biomechanical parameters of pedestrian head landing are obtained, including intracranial pressure, von Mises stress, shear stress and strain biomechanical parameters. The simulation results show that when the pedestrian head lands, the stress wave diffuses inside and outside the skull, and forms different degrees of stress concentration in the brain tissue and skull. When the pressure exceeds a certain limit, it will cause varying degrees of brain damage. The results will further support the pedestrian head injury theory and its application.