Abstract: Visibility of runway is very important to flight safety. The appearance of low cloud and haze would give rise to the low normality of schedule flight on part airports. First of all, this thesis gives aimplified analysis on some aviation accidents happening under low visibility condition in recent years, and then, the main influence factors leading to the accidents has been researched. In addition, a schedule flight of Air China-CA4461 failing on Nov. 7,2014 was analyzed as a case in order to summarize the emphases and difficulties. Finally, as for operational control, some prevention measures were put forward to prevent accidents from happening under low visibility condition.