This article deals with the living radical emulsion photopolymerization of methyl methacrylate (MMA) using a RAFT agent which plays the role of an initiator in the absence of an additional thermal initiator, a chain-transfer agent, and a surfactant. The mechanism of the formation of stable spherical polymer beads without coagulation in the absence of a surfactant and the effects of the added surfactant are studied. The molecular weights of the prepared PMMA beads are in the same range (M-n: 10(5) - 10(6) g/mol) as those obtained from a conventional emulsion polymerization. However, the molecular weight distribution (M-w/M-n; polydispersity index; PDI) is controlled to be less than 2.0. The polymer beads in diameter was significantly reduced from 300 nm without a surfactant to decreased to 50 nm upon the addition of sodium dodecyl sulfate (SDS) keeping the molecular weight and the molecular weight distribution constant. Also, the addition of SDS in the preparation of PMMA colloid results in the enhancement of the stability by exhibiting increased zeta-potential values in water.