A fused silica jet-stirred reactor (JSR) was used to study the kinetics of oxidation of M85 surrogate mixtures, i.e., methanol/surrogate gasoline (85/15 vol %). One representative of each chemical class constituting M85 was selected: iso-octane, toluene, 1-hexene, and methanol. The experiments were performed in the temperature range of 770-1140 K, at 10 atm, at four equivalence ratios covering fuel-lean to fuel-rich conditions (0.35, 0.6, 1, and 2) and with an initial fuel concentration of 0.4 mol %. Mole fraction profiles of reactants, stable intermediates, and final products were measured via sonic probe sampling followed by Fourier transform infrared spectrometry (FTIR) and gas chromatography (GC) analyses. A detailed chemical kinetic reaction mechanism resulting from the merging of validated kinetic schemes for the oxidation of the components of the present M85 surrogate (gasoline surrogate and methanol) was used. Good agreement between the experimental results and the computations was observed under the present JSR conditions.