Abstarct: One of the most important parts in mining operations is choosing the right extraction method for mineral deposits. Choosing the right mining method for exploitation of underground mine reserves is very important from the point of view of economy, performance and safety. After choosing a mining method, it is usually not possible to replace it with other methods, because this may make the project economically impossible. The present study was carried out with the aim of identifying and prioritizing the key effective factors in choosing the extraction method with fuzzy Delphi approaches and choosing the appropriate method with the OPA method. As a case study, it is focused on one of the refractory clay mines of Semnan province. Using the fuzzy Delphi method, among the 54 identified sub-criteria, 23 are capital cost sub-criteria, deposit shape, deposit slope, extractable reserve, deposit thickness, deposit depth, ore value, production rate, progress, type of discontinuities. Mechanization, monoaxial compression hanging wall, preparation time, access to technical knowledge, stress field, mineral monoaxial compression, distance of discontinuities, maintenance costs, reliability of discontinuities, land surface settlement, amount Storage, adhesion of discontinuities, monoaxial compression foot wall have been screened as effective indicators for choosing the extraction method. The result of the OPA method has been compared with the UBC quantitative method for the accuracy of the result. The room and pillar extraction method has been chosen as the most appropriate method for the refractory soil deposit.