A new strategy for parameter estimation of dynamic differential equations based on nondominated sorting genetic algorithm 11 (NSGA 11) and one-step-integral Treanor algorithm is presented. It is adopted to determine the exact model of catalytic cracking of gas oil. Compared with those conventional methods, for example, quadratic programming, the method proposed in this paper is more effective and feasible. With the parameters selected from the NSGA 11 pareto-optimal solutions, more accurate results can be obtained.