The material used in this study was the fresh Siam Semboro sweet orange peel obtained from traditional market "Pasar Tanjung" in Jember. The equipment is a set of steam distillation apparatus, separating funnel, erlenmeyer, analytical balance, measuring cup, bottle containing essential oil, aluminum foil, filter paper disc, petri dish, micro pipette, electric heater, rotary evaporator, data logger, k term thermocouple and a set of Gas Chromatography-Mass Spectroscopy analyzer (GC-MS QP2010 Plus, Shimadzu).