Abstract: According to the observed data of more than 4000 hailstone samples and 843 hailstone thin-section in Mancheng of Hebei Province in 1986-1990, the characteristics of hailstone microstructure(i. e embryos, layer, crystal and air bubble) is statistically analysed in this paper and the growth conditions(i. e envirmental temperature and altitude) of those hailstone are derived.