Abstract: Aimed to study and master the evolution of different grades about precipitation and precipitation days for giving a better suggestion of rainwater resources management and better services for agricultural production,, variation characteristics of precipitation and precipitation days were analyzed with line trend analysis and Mann-Kendall test methods based on daily precipitation data from 1951 to 2010 in Dalian. The results show that annual precipitation and rainy days decrease, and the decrease of annual precipitation days is more obvious. Light and heavy rainfall (days) shows the decreasing , moderate rainfall (days) showing the increasing , but the decreasing trend of torrential rainfall (days) is not unremarkable. The seasonal distribution of precipitation also changes significantly. Rainfall (days) in summer, autumn and winter reduce, but rainfall (days) in spring increase. Precipitation intensity has an evident increasing in spring and a decreasing in summer, autumn and winter, but the decline of precipitation intensity is not obvious in winter. On the other hand, the extreme precipitation events in spring will increase , and it is more obvious in the 21st century particularly. The obvious abrupt changes of annual precipitation days occures in 1978.