The geographic distribution of the precipitation types during the Mei-yu period in Zhejiang Province from 1971 to 1999 isanalyzed, and the characteristics of each previous Mei-yu precipitation type's changes at 500 hPa height field are studied , which finds the basicrelationship between each Mei-yu precipitation type and some foreboding factors of the global circulation in each year. The results showed thatthe different and same characteristics of the previous global circulation's changes in winter and spring are the important reasons, which result inthe Mei-yu precipitation types' respective characteristics. By analyzing some key factors dominating in earlier global circulation in three Mei-yu precipitation types, it is found that the positive or negative abnormities are the most pronounced premonitors which lead less or moreprecipitation in the northern part of Zhejiang Province during the Mei-yu period .On the other hand, it is one of the significant criterions that theextensity of the negative anomaly zone from southern Asia to the western Pacific in spring, which might predict the precipitation amount of Mei-yu in the southwestern Zhejiang Province .