Three hundred and seventy-eight isolates of Magnaporthe grisea were collected from 17 provinces (cities) in China and their geographic distribution of mating type and its fertility was tested with 4 standard isolates, KA3 and TH12 (Mat1.1) and Guy11 and TH16 (Mat1.2) provided by CIRAD. Seventythree fertile isolates of them were tested with polymorphic SCARs analysis by use PCR markers of 13 primer pairs. Preliminary results showed that the geographic distribution of M. grisea existed among isolates from the same location as well as different location and its relative relationship between fertile isolates of the fungus in China. The existence of sexual reproduction of M. grisea was explored in the field as well.