In recent years, the percentage of female teachers at all levels has been gradually increasing. Does it imply that female teachers are becoming the majority?Or is it a random phenomenon?By means of time series analysis, the author discovered:first, in elementary schools, the growth of the number of teachers accorded with that of female teachers;second, in high schools, we could predict the total number of teachers according to the number of either sex;third, in higher education, it was difficult to established which sex is the majority ;finally, we could predict the number of female students in seven years on the basis of the number of female teachers in the current year. The author also discussed that limitation of the research and possible approaches for future research.