The Mann-Kendall statistic test is a rank-based, non-parametric method. It has been widely used to estimate the significance of long-term trends in hydro-meteorological time series such as water quality, streamflow, temperature, and precipitation, etc. Temperature and precipitation are two kinds of the most important climate factors. It is of great importance for the development of economics and agriculture to analyze the long-term trends of temperature and precipitation. The long-term trend of temperature and precipitation in Shandong Province was analyzed in this paper. The data used in this paper were observed at 15 meteorological stations. The Mann-Kendall test was applied to annual and monthly temperature and precipitation time series. The results show that the temperature exhibited an increasing trend during the past 40 years, especially in winter, during which the slope was 036 ℃/(10a).The 1990s is the warmest periods in the past 40 years, and the eastern region of the study area show more obvious increasing trend. The precipitation exhibited significant decreasing trend and the slope is 305mm/a. The north-eastern area of Shandong Province contributed the most to decreasing trend of the precipitation.