The human macular pigment has been found to be composed to two chromatographically separable components, which are tentatively identified as lutein [(3R,3'R,6'R)-beta,epsilon-Carotene-3,3'-diol] and zeaxanthin [(3R,3'R)-beta,beta-Carotene-3,3'-diol]. Chromatograms of retinal extracts, obtained by HPLC on three different stationary phases, were found to match those obtained with mixtures of lutein and zeaxanthin standards. Identical retention times were confirmed by coinjection of each of the isolated components with the appropriate standard. U.V.-visible spectra of the purified components were identical in all respects with those of lutein and zeaxanthin. Further support for our identification was obtained by the preparation and chromatographic comparison of derivatives of the macular pigment and of the standards.