Abstract： To meet the demands of continuous deflection measurement at a traffic speed of 20~80 km/h, a novel method was proposed which substituted velocities of pavement deflections for absolute deflection. The measurement method and retrieve algorithm of velocities of pavement deflections with the standard loads were studied by using Doppler laser sensor. Based on the BernoulliEuler beam theory on an elastic foundation, the twoparameter solutions of deflection basin curve were deduced. Pavement deflection was inversed using velocities of pavement deflections with Newton Iteration method. The prototype system based on this method was applied to totally 40 000 km in Xinjiang, Shaanxi, Gansu, Tianjin, Hubei and other provinces in 2014. A large number of experimental data showed that the data repeatability could reach more than 95%. Compared with experimental data by Benkelman beam, its dependency was more than 90%. The method requires only a single measurement sampling and is independent to the curvature of the road, which is suitable for highspeed, nondestructive measurement. The proposed method can meet the requirements of lane by lane, continuous, non-destructive, high-density, high-speed measurement at road network level,  and has extensive promotion value.