Br phi nsted acid-surfactant-combined catalyst, dodecylbenzenesuffonic acid (DBSA), was used in catalytic dehydrative glycosylation reactions in water. I-Hydroxy sugars, such as O-benzyl-protected furanose and pyranose, reacted with alcohols and a nitrogen nucleophile in the presence of a catalytic amount of DBSA to afford the desired adducts in good yields. Detailed study of the glycosylation of 2-deoxy-D-ribofuranose showed that hydrophobicity of the substrates was important to attain higher yields. Regarding the alpha/beta selectivities, D-ribose and D-mannose derivatives gave the products in high beta- and alpha-selectivities, respectively.