The kinetics of oxidation of L-glutamine (Gln) by permanganate ion has been investigated in alkaline medium at a constant ionic strength of 0.2 mol dm-3 and at 25o C using spectrophotometric technique. A first order kinetics with respect to [permanganate] and less than unit order dependences on [Gln] and [OH- ] were revealed. No pronounced effect on the reaction rate by increasing either ionic strength or solvent polarity of the medium was recorded. Intervention of free radicals was observed in the reaction. The reaction mechanism describing the kinetic results was suggested. The final oxidation products of L-glutamine were identified as formyl propanamide, ammonia and carbon dioxide. The rate-law expression for the oxidation reaction was deduced and the reaction constants have been evaluated. The activation parameters associated with the rate-limiting step of the reaction, along with the thermodynamic quantities of the equilibrium constants have been calculated and discussed