The invention describes an environmentally friendly, sustainable and cost-effective method for preparing astaxanthin diesters of the formula 1, in which astaxanthin of the formula 2 is doubly esterified with fatty acid chlorides of the general formula 3. For this purpose, compound 2 and 3 are reacted in an organic solvent in the presence of a nitrogen-containing base of the general formula 4. The invention further relates to the non-therapeutic use of the diester 1, in which R is a residue selected from the group consisting of C13-C19-alkyl, C13-C19-alkenyl, C13-C19-alkdienyl and C13-C19-alktrienyl, in human or animal nutrition and also the therapeutic use of the diester 1 prepared according to the method as a medicament and also as an ingredient in a medicinal preparation.