Abstract: In this paper, the data of monthly mean values for water radon and level of g round water in Changli well and the rainfall data of Changli meteorological observatory from 1982~1997 are calculated. The results show a very good correlation and synchronism in m any years among them, but some differences in small time scale. These differences are corresponding to local earthquakes very ell. Thus we can make the short-term earth-quake prediction based on these differences.

Key words: Correlation analysis, Water level, Water radon, Rainfall