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The variation characteristics of visibility in the Bohai Rim region and the main contributors for different levels of visibility are examined statistically, using the daily visibility observations from 365 meteorological stations from 1980 to 2012. The results indicate that the region is mainly characterized by higher visibility in spring and autumn and lower in winter. During the period of 1980 to 2012, the maximum decline rate in annually averaged visibility is detected in the Taihang Mountains and the windward slope of the Yanshan Mountains, where are characterized by lower average visibility. Overall, water droplets are the primary contributor to visibility of less than 1 km in the Bohai Rim region, but the contribution of PM2.5 trends to increase with visibility, in the range of 1 km to 10 km visibility. Additionally, the spatial differences in the impact of water droplet and PM10、PM2.5 for different levels of visibility are addressed.