The steel deck pavement on long-span steel bridges is subjected to the heavy impact load imposed by the passage of millions of trucks during the several decades of its service life, and severe premature failures of steel deck pavement have appeared, especially the cracking. The irregularity of the pavement surface was simulated according to the power spectrum density function, and the random load was calculated according to the vehicle vibrating equation. Finite Element Method was used to build the vehicle-pavement coupling model. The effects of vehicle speed on the dynamic response of pavement were studied. Research results have proved that the maximum transversal tensile stress related to the cracking firstly increases and then decreases with the increase of vehicle speed.