The Cloud-Aerosol Transport System (CATS) lidar, on board the International Space Station (ISS), provides a new opportunity for studying aerosol vertical distributions, especially the diurnal variations from space observations. In this study, we investigate the seasonal variations and diurnal cycles of the vertical aerosol extinction coefficients (AECs) over East Asia by taking advantage of 32 months of the continuous and uniform aerosol measurements from the CATS lidar. Over the Tibetan Plateau, a belt of AECs approximately 6 km between 30° N and 38° N persistently exists in all seasons with an obviously seasonal variation. In summer, the aerosols at 6 km are identified as a mixture of both anthropogenic aerosols transported from India and coarse dust particles from Asian dust sources. In addition, the high AECs up to 8 km in summer over the Tibetan Plateau are caused by smoke aerosols from thermal dynamic processes. In fall and winter, the north slope of the plateau is continuously influenced by both dust aerosols and polluted aerosols transported upslope from the cities located in northwestern Asia at lower elevations. The diurnal variation of AECs in North China is mainly related to the diurnal variations of the transported dust and local polluted aerosols. Below 2 km, the AEC profiles in North China at 06:00 local Time (LT) and 12:00 LT are significantly higher than those at 00:00 LT and 18:00 LT, reaching the maximum at midday. The aerosol vertical profiles over the Tarim desert region in summer have obvious diurnal variations with the AECs at 12:00 LT and 18:00 LT being significantly higher than those at 00:00 LT and 06:00 LT, which are induced by the strongly diurnal variations in near-surface wind speeds. In addition, the peak of the AEC profiles has a significant seasonal variation, which is mainly determined by the boundary layer height.