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The mesomicroscale systems and radar echo characteristics during 32 shortterm strong rainfall cases in Qingdao from 2011 to 2015 are analyzed based on the CINRAD/SA radar reflectivity factor, automatic raingauge and FNL reanalysis data. The results show that the mesomicroscale systems that led to shortterm strong rainfall are the mesoscale convergence areas or lines related to the lowlevel shear line (trough), inverted typhoon trough or local convections in Southerly (Northerly). The radar echoes mostly show as a mesoscale strong echo band or local strong convective cells, and the angle between moving direction and long axis of the echo band is small, and otherwise the moving speed of local cells is slow. The shortterm strong rainfall can be divided into the continental convection type and tropical marine type by the centroid height of radar reflectivity. The average vertical profile of reflectivity of the continental convection type is generally stronger than that of the tropical marine type, which brings much stronger convective activity. The strongest reflectivity of the tropical marine type occurs in the low level with the maximum near the land surface; however, the continental convection type has clear hanging echoes with the maximum at 2 km altitude. Two different ZI relations corresponding to the two rainfall types are used for quantitative precipitation estimation. Compared with the fixed ZI relation, the result from the categorical relations shows better performance for the displacement and value of shortterm strong rainfall, and the relative error is reduced from 70% to 30% when the rainfall intensity is greater than 20 mm·h-1.