Abstract: Based on the principle of knowledge engineering,an intelligent optimization software system IOPS that can be applied to the engineering design is investigated.It is an integrated intelligent program including fourteen kinds of the algorithms for continual,discrete and stochastic variables.This system completes automatic treatment of the symbolic reasoning and numeric calculating in optimization through the concurrent proccessing of the optimization modelling,diagnose of models,selection of algorithm,made decision of multi-objective and valuation of operating parameter etc.expert systems.