In an attempt to develop a sensitive and highly reproducible method for the determination of individual tocopherols in red blood cells (RBC), high-speed liquid chromatography (HSLC) was investigated. RBC suspension was saponified after addition of tocol as an internal standard, and extracted with n-hexane. The extract was subjected to HSLC using JASCOPACK WC-03-500 column, and isopropylether・n-hexane mixture as mobile phase. A combination of saponification technique and HSLC made it possible to separate individual tocopherols and the fluorometric detection prevented the influence of interfering substances. This method gave almost 100% recovery of tocopherols, therefore it was not necessary to be corrected based on the recovery of the added radioactive tocopherols. Using this method, the tocopherols levels of plasma and RBC were determined for some human subjects, mice, rabbits, guinea pigs and rats, and for rats feeding with vitamin E-supplemented or vitamin E-deficient diet. Tocopherol ratio of RBC to plasma was different in species, but relatively constant within a same species.