Light weapon sights are widely equipped in the armed forces of different nations because they could improve the attack accuracy and lethality for the weapons. This paper briefly reviews the operation principles and features of mechanical sight, optical sight, electrooptical sight and integrated sight. The status of mechanical sight, traditional optical sight, lowlightlevel night vision sight, new electrooptical sight and integrated sight equipped in different nations worldwide is given. The development status and parameters of various typical electrooptical sights as well as simple day and night firecontrol systems are described. It is pointed out that mechanical sight and optical sight are still necessary for future light weapons. However, electrooptical sight shall prevail in equipment procurement, and light weapon sight equipped in the future shall be the integrated electrooptical sight.