Three-dimensional Image can represent target′s physical characteristic well and improve target recognition capability,but conventional optical imaging radar is limited by the array units or scan system and can not realize the imaging of moving targets.This paper combines the inverse synthetic aperture technology,laser signal and interferometric technology to suggest a new radar system which is called Inverse Synthetic Aperture 3-D Imaging LADAR.It describes the initial design of the system,analyzes the imaging theory and implement method,establishes the simulation system,finishes the imaging simulation.The simulation shows the system′s feasibility and advantage.Finally,the key problems which are needed to solve are discussed.