The kinetic parameters of thermal decomposition of initiators, azo-bis-isobutyronitrile (AIBN) and dicyclohexyl peroxydicarbonate (PC), have been measured in aqueous micellar solutions of sodium dodecylsulfate (SDS), cetyltrimethylammonium bromide (CTAB), and egg lecithin. The inhibitor technique and accepters of free radicals have been used to estimate the efficiency of the initiation during AIBN decomposition. The rate constant of PC decomposition in a SDS micellar solution is the same as in n-decane. CTAB and lecithin accelerate the rate of PC decomposition. Mechanisms of surfactant effect on the PC decomposition are discussed.