The kinetics of formation of epoxy resins derived from bisphenol-S, tetrabromobisphenol-A, and epichlorohydrin under stoichiometric conditions was considered. The kinetics of reaction was studied by taking into account the consumption of the added alkali and the epoxide group of the epoxide oligomers. The obtained results satisfactorily explained that the reactivity of bisphenol-S with epichlorohydrin is higher than that of tetrabromobisphenol-A. The rate of dehydrochlorination of chlorohydrin ether in the presence of alkali and water was much higher than that of the rate of condensation of the phenolic hydroxyl group with epichlorohydrin. The apparent reaction order of the phenolic groups with epichlorohydrin and the terminal epoxide groups in the oligomer were second order. The rate constants and reaction activation energy were determined and results discussed.