The objectives of this study were to develop Rapeseed Cultivation Simulation-Optimization-Decision Making System (Rape-CSODS), and validate it in order to design rapeseed planting, regulate and control its growth and development, and fulfill its high yield, good quality, high benefits, and standard production eventually. The models in Rape-CSODS were developed based on field experiments with 3 cultivars, 2 plant types, 6 sowing dates, and 4 sites from 2002 to 2008 in the middle and lower valley of Yangtze river in China and relative data from references of rapeseed research, employed ideas of R/WCSODS (Rice/Wheat Cultivation Simulation-Optimization-Decision Making System), then Rape-CSODS were developed through integrating rapeseed growth models, optimization models, and expert knowledge. In that the rapeseed growth models mainly included phenophase, leaf age, population dynamic, and organ forming etc., and the optimization models for rapeseed cultivation mainly included the optimum biomass, the optimum LAI, the optimum shoot and ramification number dynamics models, and the optimum decision making models for nitrogen and water etc. As a case, the system has been applied in Shandong Province in this study, and the results showed that the scheme get by this systems can increase green leaf number before over-winter, 1.1; 1000-weight, 0.2g; and rapeseed yield, 676.5 kg ha-1 at mature, comparing with rapeseed production in the same conditions. The Rape-CSODS with general adaptability, clear yield aim, better mechanism, and dynamic characteristic can get the optimum management sheet pre-planting, micro-adjustment sheet during growth for rapeseed under different climates, soil, cultivars, and yielding levels.