A new method for the catalytic didehydroxylation of vicinal diols is described. Employing a readily available low-valent rhenium carbonyl complex and a simple alcohol as a reducing agent, both terminal and internal vicinal diols are deoxygenated to olefins in good yield. The optional addition of acid (TsOH, H2SO4) provides access to lower reaction temperatures. This new system enables the transformation of a four-carbon sugar polyol into an oxygen-reduced compound, providing promising evidence for its practical application to produce unsaturated compounds from biomass-derived materials.