According to the monthly precipitation and average temperature data collected at the five typical meteorological stations from 1957 to 2008, the authors analyze the trends of precipitation and temperature in the Jianghan Plain by using Mann-kendall test with the significance level α=0.05. The results show that: there isn’t a remarkable variation trend of annual precipitation time series in the Jianghan Plain. As for the seasonal precipitation, spring and autumn precipitation have a downward trend and summer precipitation has an upward trend, but all of them are not remarkable, only winter precipitation has a remarkable upward trend. Annual average temperature time series have a remarkable upward trend, and the rate increases significantly in recent 20 years. There is a abrupt change from 1994 to 1995；after that, the upward trend becomes even more fierce.