A dual laser heterodyne velocimetry is reported. Two laser beams from different sources are respectively employed in detection and local reference. The velocity of moving surface is measured by means of Doppler effect. Dual laser heterodyne velocimetry can run in frequency down conversion mode or frequency up conversion mode. Operation mode is determined by the frequency difference of the detecting laser and the reference laser. In frequency down conversion mode, the velocimetry converts high-velocity signal’s frequency down, and then one can use a normal high-bandwidth oscillograph to measure velocities higher than 10 km/s instead of using an ultrahigh-bandwidth oscillograph, and solve the problem in which the measurements of ultrahigh-velocities depend upon ultrahigh-bandwidth oscillographs. In frequency down conversion mode, the frequency of low-velocity signal is converted up, and the measurement’s time resolution and precision increase.