Abstract: Radical polymerization of methyl methacrylate (MMA) initiated with organic hydroperoxide-amine systems was studied. t-Butyl hydroper-oxide (TBH) and cumene hydroperoxide (CHP) were used as organic hydroperoxide components, aromatic tertiary amines such as N,N-di-methyl aniline (DMA)and its p-substitued derivatives i.e. N,N-dimeth-yl-p-toluidine (DMT) ,p-nitro-N,N-dimethyl aniline (NDMA) and p-di-methylamino benzaldehyde (DMAB) were used as amine components. It was found that, the different amine structures show little effect on the Rp of MMAboth in TBH-amine or CHP-amine system. So the values of RPare not so difference whether the substituents are electron-donating groups or electron-withdrawing groups. The values of overall activation energy Ea of MMApolymerization initiated with TBH-amine and CHP-amine were determined in the range of 50-57 KJ/mole for TBH-amine systems and 39-62 KJ/mole for CHP-amine systems respectively. Furthermore, the reaction mechanism and kinetics of polymerization of MMAinitiated with ROOH-DMTsystem were studied and discussed.