Disclosed is a method for producing polyalcohols in the form of sugar alcohols from the group comprising sorbitol and mannitol and other optional C.sub.2 to C.sub.6 polyols. According to said method, a monosccharide, disaccharide, oligosaccharide, or polysaccharide containing at least one glucose unit and/or at least one fructose unit is continously reacted with hydrogen at an elevated temperature and at a great pressure in an aqueous phase in the presence of a hydrogenating catlyst based on ruthenium or ruthenium oxide so as to obtain the inventive polyalcohols. The minimum temperature is set at 100.degree. C. while the minimum pressure is set at 150 bar and the maximum dwell time of the reactants during catalytic hydrogenation is set at 600 s. The inventive method is particularly suitable for producing the sugar alcohols sorbitol and/or mannitol or C.sub.2 to C.sub.6 polyols from glucose, fructose, or disarccharides, oligosaccharides, or polysaccharides containing glucose units or fructose units, especially saccharose, practically all the used saccharides being reacted without turning into caramel. Furthermore, the yield of said sugar alcohols or C.sub.2 to C.sub.6 polyols is exceptionally high while the selectivity for the desired products can be varied in a simple manner within broad boundaries.