The absolute stereochemistry of rhodiolosides A-D (1-4), four monoterpene glycosides from the roots of Rhodiola rosea, and their aglycones, rhodiolol A (5), (-)-rosiridol (6) and sachalinol A (7), were reinvestigated. It was found that the absolute configurations of C-4 in these compounds, previously assigned to be 4-R, should be revised to 4-S.