Atmospheric particles, a complex mixture of inorganic salts, organic compounds and water, can continually undergo heterogeneous oxidation initiated by gas-phase oxidants at the particle surface. We found that ammonium sulfate can decelerate the rate of heterogeneous OH reaction with 2-methyltetrols when the inorganic-to-organic mass ratio increases. These results would suggest 2-methyltetrols are likely chemically stable against heterogeneous OH oxidation in the atmosphere.