An extremely severe precipitation event took place in Beijing during 15-17 July 2018. This event was characterized by long duration, large accumulated precipitation amount and locally strong intensity. According to the features of hourly precipitation decrease stage by stage, the three types of convective storms and their precipitation characteristics are analyzed and compared. The results show that the extreme precipitation at the edge of the subtropical high in the morning of 16 July was mainly caused by the low-echo-centroid convective storms, during which the warm and wet layer was deep and the vertical wind shear was weak. The characteristics of convective storms, 〖JP2〗which were similar to the severe tropical precipi-〖JP〗tation storms, along with the impact of “train effect” were the direct causes for the extreme severe precipitation in Minyun District of Beijing. The high-echo-centroid convective storms mainly took place during the daytime of 16 to the early morning of 17 July, when the westerly trough and the subtropical high affected this area together. During this period, the dry air intruded into the middle layer and the vertical wind shear of the whole layer was stronger. The convective storms had some characteristics such as high-echo-centroid, draping structure, strong local features and rapid movement, and the maximum precipitation intensity caused by the high-echo-centriod convective storms was weaker than it caused by low-echo-centroid convective storms. Hybrid convective storms corresponded to heavy precipitation during the transit of westerly trough on the 17th July. Compared with the early stage, the energy and water vapor conditions during this period decreased significantly. The echoes and precipitation intensity of hybrid convective storms were the weakest of the three types. The intensity and magnitudes of precipitation in different stages of this process were determined by the corresponding environmental conditions, structural characteristics and moving propagation characteristics of different types of convective storms.