Fe-Al compound at the interface of steel-mushy AI 28Pb bonding plate was studied quantitatively. The relationship between ratio of Fe AI compound at interface and bonding parameters such as preheating temperature of steel plate, solid volurne fraction of Al-28Pb slurry and roiling speed, was established by artificial neural networks perfectly. The results show that when the bonding parameters are 546℃ for preheating temperature of steel plate, 43.5% for solid volume fraction of Al-28Pb slurry and 8.6mm/s for rolling speed, the reasonable ratio of Fe-Al compound corresponding to the largest interracial shear strength of bonding plate is obtained as 71.5%. This tea sonable ratio of Fe-Al compound is a quantitative criterion of interracial emhrittlement, that is, when the ratio of Fe-Al compound at interface is larger than 71.5%, interracial embrittlement will occur.