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With the 57year Tropical Cyclone (TC) data from 1950 to 2006, the climatic characteristics of TCs influencing Zhejiang are analyzed. The results indicate that since the 1990s, the TCs influencing or landing Zhejiang show a increasing trend, which is different from the decreasing trend of TCs influencing or landing on the whole China. In TCs both influencing and landing on Zhejiang there exist variation with the long periods being quasi15 years and quasi25 years, and the short periods being the quasi5 years and quasi8 years, respectively. The average source region is more northward and eastward for TCs influencing Zhejiang than those influencing China, which is more westward and northward than normal from the 1990s. In addition, the East Asian circulation factors during July and September are analyzed, and the results show that the structure of the circulation system in the years with more TCs influencing Zhejiang is much different from the years with less TCs influencing Zhejiang.