4-Methylene-1,3-dioxolane derivatives such as 2-thienyl-4-methylene-1,3-dioxolane (TMD), 2-thienyl-2-methyl-4-methylene-1,3-dioxolane (TMMD), and 2-furyl-4-methylene-1,3-dioxolane (FMD) were synthesized, and their polymerization behaviors were investigated under various conditions. These monomers containing 1,3-dioxolane moiety were homopolymerized with boron trifluoride as a cationic initiator to give a soluble polymer with low molecular weight. In the presence of radical initiator, although no homopolymerization occurred, it was observed that TMD, TMMD, and FMD were readily copolymerized with a comonomer. The IR and NMR spectra suggest that the homopolymerization proceeds through ring-opening process to give polyketoether structure having thieny1 or furyl group.