Abstract: Resource assessment is the basis for decision-making in petroleum exploration, and it is one of the important work for formulating energy development strategy and industry development plan of the government. The difficulties and characteristics of Sinopec’s new round of resource assessment against the new situations are analyzed, and the overall idea and technical framework of resource assessment during the 13^th Five-Year Plan period are demonstrated in detail. As a result, a series of oil and gas resource assessment technologies and software platforms with Sinopec’s characteristics are innovatively developed, including a complete source rock evolution simulation technology from hydrocarbon generation to expulsion and retention, “conventional-unconventional” integrated TSM basin modeling technology, shale oil and gas resources classification and evaluation technology based on maturity and pressure coefficient, “geology-economy-ecology” integrated oil and gas resource assessment technology. Furthermore, on the basis of resource assessment during the 13^th Five-Year Plan period, the key research directions of resource assessment in the future are proposed as follows: (1) 3D hydrocarbon migration and accumulation simulation technology of complex geological conditions and special types of oil and gas reservoirs; (2) Zoning schemes for various types of basins and corresponding resource calculation and splitting technology; (3) Integrated oil and gas resource assessment system based on big data and intelligent platform; (4) Comprehensive evaluation technology of oil and gas co-associated resources.