The choice of financial regime in oil-rich countries depends on proven reserves, exploration and production costs, geological characteristics, political risks, and oil market conditions. In this article, CONTRACTual components of three CONTRACTs IPC, BUYBACK, and PSC are introduced using Visual Basic programming language, and a model structure for a 42-season period scenar-io with oil prices is created. Also, modeling based on the parameters of the Shadegan oil field is another innovation of this work. The aim of this research is to investigate the effective indica-tors in the oil and gas industry CONTRACTs based on oil price scenarios. The results of this study show that many of the constraints of the reservoir owner country have been modified in the direction of protecting oil fields and effectively controlling CONTRACTor's fees in modified mutual agreement and production sharing CONTRACTs, and the financial system of the new oil CONTRACTs is more efficient in case of an oil price increase and in the final years of production compared to production sharing and BUYBACK CONTRACTs. In this study, comparing indicators such as internal rate of return, payback period, profitability index, and the share of both parties in the CONTRACT based on real and simulated data showed that entering into new oil CONTRACTs in Iran, especially IPC in the Shadegan oil field, can protect the oil field, prevent uncontrolled oil extraction, and control CONTRACTor's revenues, leading to lower costs and higher revenues compared to BUYBACK and production sharing CONTRACTs for the host country (Iran).