Through experiments and model simulation, this paper had a comprehensive study on the determination and prediction of the bubble point pressure(BPP) for the CO2-oil system. The result indicates that The reservoir fluid and CO2 can normally reach the one-contact miscible state above the CO2 concentration of 60 mol%. For different oil samples of a certain reservoir, the curves of the relative BPP can be regressed to get a single curve. These curves can be used to estimate the BPP of any unknown oil-CO2 mixture in the reservoir. The calculation result of the advanced PREOS is accord with the experiment result, which is better model simulation.