Abstract:In this paper, by using of the Meiyu data of 52 years from 1951 to 2002 in Anhui province, the first day, the last day, the length and the total precipitations of the Meiyu period are discussed. The results show that the beginning of the Meiyu period is always in the second pentad or the fourth pentad in June, and the end of the Meiyu period is usually in second pentad in July. There are correlativities between the first day of the Meiyu period and the weather pattern, the length of the Meiyu period, the total precipitations of the Meiyu period. The characteristic of the interannual changes about the Meiyu period that we found in this paper will develop our skills about how to make the more accurate forecast about the first day, the last day, the length and the total precipitations of the Meiyu period. Furthermore, it will help us to do our flood- control and drought-resistance services better.