Abstract: Based on the 14 years(2006-2019) CALIOP data and up-to-date lidar aerosol classification method, the dominant aerosol types and the vertical distribution characteristics over the Bohai and Yellow Sea within the height range of 0.28-8.17 km were identified, and the long-term variability and seasonality were revealed. (1) The dominant aerosol types in the study area are Dusty Marine(36%), Dust(25%), Clean Marine(17%), Elevated Smoke(11%) and Polluted Dust(9%) (totally>97%), with the three types of aerosol related to dust accounting for about 70%. (2) The vertical distribution of various types of aerosols has distinct characteristics. Aerosols of Clean Marine and Dusty Marine are mainly found in the atmosphere with height below 2.5 km. Polluted Dust and Elevated Smoke are mainly above 2.5 km. The proportion of Dust aerosols increases with height. (3) In regards of the long-term variability, the percentages of Polluted Dust show a fluctuating descending trend during the past 14 years, whereas that of Clean Marine aerosol increases steadily, and that of Elevated Smoke decreases monotonously. (4) The proportion and vertical distribution of various types of aerosols exhibit obvious seasonal variability.