In recent years, China's oil and gas dependence on foreign countries has been rising, coupled with the fluctuation of international oil prices, China's oil and gas companies in overseas development benefits need to be guaranteed, and the importance of block selection is increasingly prominent.Block selection model is established for overseas onshore conventional oil and gas exploration projects,and the influencing factors of oil and gas selection are summarized into economic value, risk and strategic value.In order to make the evaluation results satisfy decision makers to the greatest extent,this paper conducts a comprehensive evaluation of the block based on the utility theory and the analysis of influencing factors of block selection.The weighted utility matrix was established by defining the utility function and combining the subjective and objective weights,and the proximity of each block to the ideal block was calculated by the projection method.Finally, through the case analysis of the model application, the corresponding block ordering of decision makers with different preferences is given.The model provides reference for the investment decision making of oil companies.