Abstract: The characteristics of chemical component and agrochemistry behavior of slog containing silicon were studied in this paper. The results showed that the main chemical components in slog containing silicon were SiO2, CaO, Al2O3, MgO, Fe2O3, MnO,their contents were individually 260.7-382.8、1.7-494.6、43.6-338.1、0.2-84.5、4.9-378.6、0.9-106.7 g/kg. The content of SiO2 was the most stable; There were almost the same microelement contents of Zn、Cu、Mo、B in slog as that in soil. The most contents of heavy metal were below standards provided by country and they existed in combining form and low activity. The content of available SiO2 was 0.79-9.11 g/kg, the release rate of P were different in different types of slog. Freundlish formula could simulate well to the release process of silicon in slog containing silicon, and the parameter b value could reflect release ability of P. The availability of P in slog containing silicon was low. Slog containing silicon had effects of absorption and fixation to P added, and fixation amount increased obviously by the increasing of fineness and water content of slog. No matter slog containing silicon was manured into soil after size degradation or used as material of multivariate compound fertilizer, the fixation of slog to P must be taken into account.