The invention provides a method for separating and purifying all-trans xanthophyl powder with high content from a tagetes oleoresin. The method comprises the following steps of: dissolving the tagetes oleoresin in a non-polar solvent under the heating condition; adding a phase-shift catalyst into the mixture; saponifying the mixture under the alkaline heating condition; dispersing the mixture by using a polar solvent or aqueous solution thereof; and filtering and drying the mixture under vacuum to obtain the xanthophyl powder with the total carotenoids content of over 98 percent and the proportion of all-trans xanthophyl of over 92 percent. The product meets the standard of the United States pharmacopoeia, and the stacking density of the product is more than that of the xanthophyl crystal so as to ensure convenient storage, transportation and application; and the method has the advantages of simplicity and convenience and high purity of the product and is suitable for industrial production.