Using poly(dimethylsiloxane) membranes, the sorption amount of dimethylcarbonate-methanol mixture into the membranes at the equilibrium was measured and pervaporation of dimethylcarbonate-methanol mixture was performed. The equilibrium concentration of the mixture in the membrane increased with increasing dimethylcarbonate concentration in the liquid phase. The membrane was permselective to dimethylcarbonate in the range of dimethylcarbonate weight fraction in the feed up to 0.8 in pervaporation. The permeation fluxes of both components increased and the separation factor remained almost constant as the operating temperature increased. The permeation fluxes through the membrane were analyzed by the solution-diffusion model considering the swelling effect of dimethylcarbonate on the membrane, and diffusion coefficients and swelling parameters were evaluated. The calculated values of separation factor based on the model were in good agreement with the experimental ones.