Biodiesel is currently considered as the most promising substitute for diesel fuel because of its similar properties to diesel. This study presents the use of the supercritical methanol method in the production of biodiesel from Croton megalocarpus oil. The reaction parameters such as methanol-to-oil ratio, reaction temperature and reaction time were varied to obtain the optimal reaction conditions by design of experiment, specifically, response surface methodology based on three-variable central composite design with a=2. It has been shown that it is possible to achieve methyl ester yields as high as 74.91% with reaction conditions such as 50:1 methanol-to-oil molar ratio, 330 degrees C reaction temperature and a reaction period of 20 min. However, Croton-based biodiesel did not sustain higher temperatures due to decomposition of polyunsaturated methyl linoleate, which is dominant in biodiesel. Lower yields were observed when higher temperatures were used during the optimization process. The supercritical methanol method showed competitive biodiesel yields when compared with catalytic methods.