The volatilization behavior of Seleenium in coal / coal char was studied by determining the concentration of Se with AFS at H2O(Ar) atmosphere in high-temperature tube furnace. The inhibition effects on the volatilization of Se with calcium-based material (CaO) and nano materials Fe3O4 as absorbents were studied during coal gasification. The results show that the volatilization rates of Se, rising with the temperature of gasification, can be effectively controlled with the absorbent of CaO. Because CaO can reacts with Se produce CaSeO4, a more stable compoud. Nano-Fe3O4 can enhance the ability of CaO to inhibit the volatilization of selenium, it is because not only can promote more CaSeO4, while also reducing the possibility of its decomposition.