Nowadays, the catalytic conversion of lignocellulosic biomass is the topic of many investigations.Interesting compounds that can be produced from the carbohydrate part of lignocellulose are sugar alcohols. Hence, these products production is of prime interest due to their wide use in chemical 2 industries. They can be synthesized by the hydrogenation of sugar monomers in the presence of heterogeneous catalysts that are not always stable in water. Herein, we show that a commercial Ru/Al2O3 catalyst can be used to selectively convert first glucose to sorbitol with a yield around 97 % under optimized conditions. The reaction pathway was determined by the analysis of intermediate compounds. This catalyst was stable up to 10 reaction cycles due to the nature of the support and the Ru particle sizes. I was active in the hydrogenation of sugars such as glucose, fructose, mannose, galactose and xylose to sugar alcohols.