A new dammarane glycoside named ginsenoside $Rf_{2}$ has been isolated from Korean red ginseng (Panax ginseng) and its chemical structure has been elucidated as $6-O-[{alpha}-L-rham-nopyranosyl (1{ ightarrow}2){eta}-D-glucopyranosyl]$$dammarane-3{eta}, 6{alpa}, 12{eta}$, 20(R), 25-pentol by chemical and spectral methods.