A novel 3D laser imaging technique which works at push broom mode is proposed.The digital micromirror device(DMD) is used to complete the spatial transformation of laser echo’s time of flight(TOF).Because the flight time of echo pulse changes with the distance of the targets,the micro mirrors transform from a status to another when pulses arrive at the DMD,and the focal plane array(FPA) of the receiver sensors shows the different relative position streaks.The section range profile of the target was rebuilt by the relative distances of streaks.Comparing with the other 3D imaging technologies,this technology has the advantages of high imaging rate,large field of view,simple structure and small volume etc.