The anionic polymerization of phenyl glycidyl ether (PGE) in miniemulsion was investigated. Didodecyldimethylammonium hydroxide was used as an inisurf, i.e., exhibiting both surface-active properties and the ability to initiate polymerization by means of its hydroxide counterion. Stable miniemulsions were obtained by ultrasonication, and then polymerization was carried out to produce genuine R,ω-dihydroxylated polyether chains as revealed by 1 H NMR, FTIR, or mass spectroscopic methods. The average molecular weight could be increased by varying the initiator concentration, type and concentration of surfactants or by adding a cosurfactant (typically alcohol). In all attempts, polymer chains increased in size with conversion but remained small, with a critical polymerization degree of DP max ) 8. A mechanism was proposed to account for these results. From these observations, phenyl glycidyl ether could be used as a model monomer to investigate ionic polymerization in miniemulsion.