A newly devised continuous flow stirred tank reactor (CSTR) was employed for the study of kinetics of supercritical water oxidation (SCWO) of methanol near the critical point (390-430 degreesC, 24.7 MPa), where the reaction progress was analyzed by means of Raman spectroscopy. The production of CH2O, CO, and CO2 through the oxidation reaction was directly detected. Methanol conversion as a function of residence time could be analyzed on the basis of a simple first-order CSTR reaction model including phenomenological induction time. The overall reaction rate thus obtained was well-reproduced through simulation by a detailed chemical kinetics model, which supports the belief that the radical chain reaction mechanism is responsible for methanol SCWO even near the critical point.