The polymerization of methyl methacrylate (MMA) initiated with organic peroxide，such as benzoyl peroxide (BPO)，lauroyl peroxide (LPO)，and N，N—di(2-hydroxyalkyl)-p-toluid-ine，such as N，N—di(2-hydroxyethyl)-p-toluidine(DHET)，N，N-di(2-hydroxypropyl)一p-to-luidine(DHPT)，or tertiary aromatic amine such as N，N—dimethyl-P-toluidine(DMT)，N，N-dimethyl aniline (DMA) systems has been studied．The polymerization rate Rp

overall acti-vation energy of polymerization Ea，and the rate equation of MMA polymerization in toluene were determined respectively．It was found that the order of Rp as follows：BPO-DHET>BPO-DHPT>BPO—DMT>BPO—DMA>BPO，and the values of Ea for BPO-Amine systems were always smaller than that of BPO alone．In the MMA curing reaction using the BPO-Am-ine initiation systems can decrease the curing time and shorten the time required to reach the peak temperature．From the ESR studies on the free radical intermediates produced from the BPO-Amine-MNP (2-methyb2-nitrosopropane) systems，it reveals the formation of radicals 1—4(see Table 5)．The UV spectra of PMMA solutions reveal that the DHET and DHPT moieties are present as the end groups of polymer obtained by using BPO—DHET and BPO—DHPT initiation sy-stems．Based on these results．the initiation mechanism for BPO一DHET and BPO一DHPT initia—tion systems were proposed．