The COVID-19 disease causes severe symptoms like fever, cough, and respiratory disorder like streptococcus pneumonia. Essential oil in cajuput is oil is believed to have effect to reduce respiratory disorder due to COVID-19. While the cajuput oil is not proven to prevent or to heal COVID-19 patients, the treatments using cajuput oil are proven helpful to ease the symptoms. Indonesia as a tropical country has large-scale cultivation of cajuput plants, for example in 2017, Sumedang and Majalengka areas produced up to 4 tons raw material or 10 kg in a day. In producing cajuput oil, there are some steps required for oil extraction and distillation including modified steam distillation method used in this study. This method of essential oil extraction process may use a large amount of heat to produce steam. Geothermal residual heat in the form of brine can be an alternative used to extract eucalyptus oil on small scale. This study shows the material balance analysis for the cajuput oil production with 10 kg cajuput leaves per day from Sumedang and Majalengka areas using Wayang Windu geothermal power plant brine at 180.7°C with 0.05 kg/s mass flow rate. Wayang Windu geothermal power plant itself was chosen because the distance is not too far from cajuput source, which is around 99.7 km. In this study the cajuput oil extraction produces around 57.918 × 10−3 kg of cajuput oil for daily production time 100 min/day.