FACTORS AFFECTING THE PRODUCTION OF OYSTER MUSHROOM IN BANYUMAS DISTRICT. 2020. GHEFIRA SARASWATI (Thesis is guided by NUR RAHMAWATI & FRANCY RISVANSUNA F). The purpose of this study is to know the profile of oyster mushroom farmers, to determine the factors that affect oyster mushroom production, to analyze the costs and the benefits of oyster mushroom farming and the feasibility of oyster mushroom farming as seen from RC Ratio in Banyumas district. The data collection was carried out by distributing questionnaires and interviews with 34 oyster mushroom farmers using the snowball sampling method. This study uses descriptive analysis techniques for farmer profiles and farm characteristics, oyster mushroom factors production are analyzed by multiple regression analysis methods using the SPSS application, then using farm analysis to determine the costs, benefits, and feasibility of the RC Ratio. The results shows that the factors of sawdust, lime and seeds significantly affected to the production of oyster mushrooms. Rice bran, labor, sterilization time, and the inoculation process do not significantly affect to the production of oyster mushrooms. Meanwhile, farm analyzing shows that the total cost of producing oyster mushrooms during one season with an average of 2.251 logs is Rp 5.831.693, farming profits are Rp 1.965.924, and RC Ratio is 1,34, which means that oyster mushroom farming is feasible to run.