Phosphorus-containing vinyl ether monomers and 1-propenyl ether monomers were prepared by the regioselective addition reaction of glycidyl vinyl ether (GVE) or 1-propenyl glycidyl ether with diaryl phosphonates with quaternary onium salts as catalysts. The reaction of GVE with bis(4-chlorophenyl) phenylphosphonate gave bis[1-(4-chlorophenoxy methyl)-2-(vinyloxy)ethyl]phenylphosphonate in a 68% yield. The structures of the resulting phosphorus-containing vinyl ether monomers and 1-propenyl ether monomers were confirmed by IR and H-1 NMR spectra and elemental analysis. Photoinitiated cationic polymerizations of the resulting phosphorus-containing vinyl ether monomers and I-propenyl ether monomers were investigated with photoacid generators. The polymerization of vinyl ether groups and 1-propenyl ether groups of the obtained monomers proceeded very smoothly with a sulfonium-type cationic photoinitiator, bis [4-(diphenylsulfonio)phenyl]sulfide-bis(hexafluorophosphate), upon UV irradiation. (c) 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3105-3115, 2005.