Abstract: Based on the meteorological observation data such as precipitation and temperature in Shenzhen and surrounding cities, the characteristics of precipitation multi-year variation and the distribution of rain island in Shenzhen are analyzed, as well as the related influencing factors. The results are shown as follows. The annual precipitation in Shenzhen shows an oscillating variation, especially the inter-annual fluctuation in the 2000s is the largest, mainly due to the cloud condensation nodule concentration variation. Under the background of urbanization, it shows a certain increasing trend of the rainfall intensity in Shenzhen and surrounding cities, due to thermodynamic factor and other factors. Urbanization and topography together determine the rain island distribution pattern in Shenzhen. The rain island distribution is mainly affected by topography in the early stage of the flood season; that in later flood season is mainly affected by urbanization; that in non-flood season is affected both by urbanization and topography. In Shenzhen, heavy rain is the determining factor of the inter-annual precipitation variation and the rain island distribution.