The synthesis of a new methylene-(vinyl alcohol) copolymer, poly((vinyl alcohol)(2)-altmethylene) (MVOH), by ring-opening metathesis polymerization with ruthenium catalysts is reported. Unsaturated cyclic 1,3-diols were protected with a di-tert-butylsilyl group to form strained cyclic olefins. The molecular weights of the polymers were controlled by varying the monomer-to-catalyst ratios or by the addition of a chain transfer agent. Hydrogenation and subsequent deprotection of the ROMP polymers yield the MVOH copolymer structure which was confirmed by H-1 NMR and C-13 NMR spectroscopies. Thermal properties of the corresponding MVOH copolymer are reported.