In frontal crashes,the accelerator pedal has a direct impact on the driver's feet，and its mechanical property is one of the main factors affecting the driver's lower extremity injury.However,in the current simulation researches on the driver's lower extremity injury,the accelerator pedal is often ignored or simulated by using the ri- gid body model,which cannot accurately reflect the effect of the pedal on the driver's lower extremity and cannot be used to analyze the effect of the pedal fracture on the driver's lower extremity injury.In order to solve these prob- lems,a detailed finite element model of the accelerator pedal is constructed,and it is proved to be effective through six groups of pedal component tests.Based on this model,the effects of the pedal friction coefficient,the rotation stiffness,the travel and the intrusion volume,the fracture torque on the driver's lower extremity injury are re- vealed.The results show that the fracture torque of the pedal has a significant effect on the lower extremity injury.Specifically,reducing the fracture torque can greatly decrease the driver's tibia force and tibia index,thus reducing the risk of the lower extremity injury.This research result also highlights the value of the breakable pedal designing on the driver's lower extremity protection,and can be taken as a reference for the structure design of accelerator pedals.