Using the meteorological data set in 1951-1990 over 160 stations,prepared by NMC in Beijing, a series of 10 - year running mean curves of both the yearly and monthly temperature and total precipitation over the country are obtained and analyzed. Then climate change in China and its regional and seasonal characteristics are discussed in some extent. The annual potential crop productivity at each station and then in each climate region as well as the country as a whole are calculated. Based on these calculations, the influence of climate change on the potential crop productivity is discussed preliminarily.