Based on the meteorological and environmental observation data, the variation characteristics and meteorological conditions of haze in Lianyungang City were analyzed during 2008-2018. The synoptic backgrounds and pollutant sources of moderate and heavy haze events in this region were also emphatically discussed. The results indicated that the number of haze days in Lianyungang main urban area increased significantly from 2011, which reached the peak from 2013 to 2015, and then decreased year by year. The haze days appeared most frequently in winter while the number of heavy haze days in January ranked the most. The wind speed 1-2 m·s-1 was most conducive to the formation of moderate and heavy haze. The frequencies of haze hours ranked higher under the wind directions of WNW, WSW and SSW in Lianyun-gang main urban area, and the frequency of haze hours under easterly wind from the sea was also higher duing to factors like terrain features and industrial layout. The haze appeared at a highest frequency with the relative humidity between 70% and 80%, while higher relative humidity was more conducive to the formation of moderate and heavy haze hours. The correlation coefficients of PM2.5 concentration and meteo-rological factors such as visibility, wind speed and relative humidity were higher than that of PM10. The surface circulation backgrounds of moderate and heavy haze events can be divided into five types, which were low pressure or inverted trough type, prefrontal type, front of high pressure type, back of high pressure type and uniform pressure field type, among which the uniform pressure field type accounted for the largest proportion of 35.8%. The inversion layer played an important role in the formation of moderate and heavy haze events, and the average intensity and frequency of inversion at 08:00 BT and 20:00 BT were both higher than that at 14:00 BT. Analysis of trajectory clustering showed that the source, path and moving distance of air masses corresponding to moderate and heavy haze events under different weather types were of significant differences.