Abstract: The method of vehicle-bridge coupling vibration considering lateral vibration of cables was adopted for analyzing traffic vibration responses of steel and CFRP cable-stayed bridges with spans ranging from 600m to 1400m. The influences of vehicle model and running speed of vehicle were investigated, and the dynamic impact factors of cable-stayed bridges were discussed. The results show that the static displacement and the long-period vibrations are the main components of traffic vibration responses of long-span cable-stayed bridge girders. The lateral vibration of cables is not obvious. The difference in vehicle models has little effect on structure dynamic responses. The impact factors of structure increases with increasing speed of vehicle. The dynamic responses of steel and CFRP cable-stayed bridges are nearly identical. The impact factors of cable-stayed bridge have a great variation and are related to the type of members.