[en] In order to detect dynamic deflection rapidly and continuously, a dynamic model under traffic load of asphalt pavement finite element was built, dynamic deflection with different traffic speeds and different point were studied; the dynamic deflection with different thickness of pavement layers and different dynamic modulus were also studied. Results show that the dynamic deflection is different with different traffic, the higher the speed the smaller the deflection, and the maximum deflection lags the peak traffic loads; road pavement thickness increased significantly reduced dynamic deflection, the order of thickness impact dynamic deflection was the surface layer, the base and subbase; the layers modulus increases the dynamic deflection reduced. Findings contribute to developing continuous and rapid dynamic deflection testing equipment based on dynamic deflection characteristics of the road surface. (paper)