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Based on the precipitation data from 86 observational stations in Guangdong Province and the NCEP reanalysis data from 1981 to 2019, and the MICAPS radiosonde data from 2005 to 2020, the temporal and spatial distribution, synoptic circulation and the radiosonde characteristics of winter rainstorm events in Guangdong are studied. The results show: (1) The winter rainstorms in Guangdong show ununiform distributions in different areas. Generally, more rainstorms occur in north and east than in south and west, and there are 0.25 winter rainstorms that occur in Guangdong per year on average. The rainstorm events occurring at less than 10 stations account for 65.6% of total rainstorm events in winter, indicating that the winter rainstorm events usually occur in small regions. (2) Winter rainstorms occurring in February take the largest percentage, while rainstorms in December are the least. Convection is usually found along with the rainstorms in February. Rainstorm events occurred between 1981 and 1990, 2011 and 2019 are more than those of other two decades in Guangdong. (3) Most winter rainstorms occur in steady atmospheric stratification with moderate K index and Δ〖WTBX〗T〖WTBZ〗, low CAPE, 〖JP2〗high SI and IQ index. (4) The main influencing systems include the eastward moving south westerly trough at 500 hPa, steady southerly airflows and cold shear line at 850 hPa, and the southward moving cold front at ground. Dominant background synoptic circulation that brings winter rainstorms can be classified into 4 patterns, including the shear linecold front pattern, the southerly airflowcold front pattern, the southerly airflowtransformed cold high ridge pattern, and the southerly airflowsouthwest depression pattern. 〖JP〗