Abstract: Based on the observational data of atmospheric visibility and some meteorological parameters (relative humidity,wind speed,air temperature,and atmospheric pressure) at ground from 2011 to 2012 in Gaizhou of Liaoning province,the monthly and daily variations of atmospheric visibility as well as its correlation with meteorological parameters were analyzed.The results show that the high visibility events usually occur in March and October in Gaizhou,and the low visibility ones mostly occur from June to August.The visibility in summer is the lowest during a whole year,and its largest visibility appears at 14:00,lower one at 08:00,and the lowest at 20:00 during a day.The correlation of atmospheric visibility with relative humidity is the best,and followed by wind speed,air temperature,and atmospheric pressure.As relative humidity is larger than 80.0%,the minimum atmospheric visibility is in the range of 10.4±3.2 km,and the correlation coefficients between visibility and atmospheric pressure,air temperature,and relative humidity are -0.52,0.51 and -0.52,respectively.Low visibility events (<10 km) in Gaizhou mainly result from higher air temperature and relative humidity,as well as smaller wind speed and atmospheric pressure.