The corrosion behavior of three kinds of spinel clinkers containing different MgO content was investigated base on the reaction with ladle slag between 150$0^{circ}C$ and 1$600^{circ}C$. The amount of MgO.(Al, Fe)2O3 complex spinel formed near the hot face was proportional to the MgO content in spinel clinkers and the complex spinel depressed the slag penetration into the spinel clinkers. he free MgO and spinel minerals mainly trapped Fe2O3 among the slag components. The CaO-Al2O3 compound were formed by the reaction between the free Al2O3 in spinel clinker and the CaO component in slag and he slag penetration into spinel clinkers was retarded by compounds