The effects of solvents on reaction rate as well as the rate constants of initiation, propagationtermination, decomposition, and the overall reaction of a heterogeneous-free-radical reaction system were obtained. Both aprotic solvents, such as ethyl acetate, carbon tetrachloride, acetone, and acetonitrile, and protic solvents, such as acetic acid and propionic acid, were used. The main properties of solvents are electrostatic force a{, dispersion force <5S, and specific solvation ET. The results reveal that the properties of solvents significantly affected the activation energy and activation entropy of the reaction steps. The initiation rate of aldehyde oxidation was studied by the inhibitor