On the basis of formulating the 9-lump kinetic model for gasoline catalytic upgrading and the 12-lump kinetic model for heavy oil FCC,this paper is aimed at development of a combined kinetic model fora typical FDFCC process after analyzing the coupled relationship and combination of these two models.Themodel is also verified by using commercial data,the results of which showed that the model can betterpredict the product yields and their quality,with the relative errors between the main products of the unit andcommercial data being less than five percent.Furthermore,the combined model is used to predict andoptimize the operating conditions for gasoline riser and heavy oil riser in FDFCC.So this paper can offersome guidance for the processing of FDFCC and is instructive to model research and development of suchmulti-reactor process and combined process. On the basis of formulating the 9-lump kinetic model for gasoline catalytic upgrading and the 12-lump kinetic model for heavy oil FCC, this paper is aimed at development of a combined kinetic model fora typical FDFCC process after analyzing the coupled relationship and combination of the two models.Themodel is also verified by using commercial data, the results of which showed that the model can betterpredict the product yields and their quality, with the relative errors between the main products of the unit andcommercial data being less than five percent.Furthermore , the combined model is used to predict and optimize the operating conditions for gasoline riser and heavy oil riser in FDFCC. So this paper can offersome guidance for the processing of FDFCC and is instructive to model research and development of such multi-reactor process and combined process.