Adopting the fuzzy fractal method which combines fuzzy set theory and fractal theory, the fuzzy fractal values of dynamic water -level in yu -01 well, Fanxian county, Henan Province, are calculated, and the relationship between the fuzzy fractal value and three earthquakes (Ningjin M_S5.8 in 1981, Heze M_S5.9 in 1983, and Renxian M_S5.0 in 1985)is analysed. The result shows an abnormal characteristic that the fuzzy fractal value fell down to less than 0.75 apparently before three earthquakes, and the larger the degree of earthquake is and the smaller the epicentral distance is, the longer the time of abnormal characteristic last.