The laser guidance weapon is the important target of the port wharf′s air defense.Signal characteristics and air-to-ground attack modes of foreign typical laser guidance weapons were analyzed.For air defense characteristics of the island and port,multi-level electro-optic countermeasure mode was analyzed,and the basic principles of comprehensive electro-optic countermeasure methods including laser deception jamming,laser damage jamming and smoke jamming were proposed in space layout and using sequence.