Several β-d-ribonucleosides were synthesized in high yields under mild conditions byN-glycosylations of methyl 2,3,5-tri-O-benzoyl-β-d-ribofuranosyl carbonate (1) with trimethylsilylated nucleoside bases in acetonitrile using a catalytic amount of metal iodide such as SnI2, SbI3or TeI4. A deprotection ofN6-benzoyl group of coupling product took place to a considerable extent whenN6-benzoyl-N6,N9-bis(trimethylsilyl)adenine was employed as a nucleoside base using SnI2or SnCI2as a catalyst while it was minimized when SbI3or TeI4was used. Further, theN-glycosylation of1with 7-trimethylsilyltheophylline in the presence of a catalytic amount of metal iodide was more effectively achieved in nitrile solvents other than acetonitrile.