Six chemical components I-IV were isolated from the roots of Rhodiola crenulata (Crassulaceae). Five (I-V) of them were identified as known salidroside (I), p-tyrosol(II), pyrogallol, gallic acid, and beta-sitosterol, based on comparison of its Rf(TLC), mmp and spectral data with those of authentic samples. The sixth component was found to be a new delta 1-isopentenyl-3-O-beta-D-glucopyranoside and named crenulatin(VI). Its structure was confirmed on the basis of its spectral data (IR, MS, 1H- and 13C-NMR).