The invention discloses a method for separating and preparing five high-purity anthocyanidin monomers from grape skins, relating to the preparation of natural pigments and belonging to the fields of food safety and food analytic chemistry. The method comprises the following steps of: firstly, carrying out anthocyanidin digestion on carbernet sauvignon grape skins to obtain crude extractive of anthocyanidin; then purifying the crude extractive by using XAD-7HP macroporous resin, and removing most of moisture absorption components such as saccharides, inorganic salts, phlegmatic temperament and the like in the crude extractive; and carrying out preparative liquid phase separation on the extractive of anthocyanidin subjected to the preliminary purification to obtain the high-purity monomers of the anthocyanidin. The method has the advantages of only using alcohol and acid as a solvent in stages of extraction, purification and separation in the preparation of the anthocyanidin and being environment-friendly, simple, convenient and feasible. The five anthocyanidin monomers obtained after purification are respectively delphinidin glucoside, 3'-methyl delphinidin glucoside, dimethyl delphinidin glucoside, dimethyl delphinidin acetylation glucoside, and dimethyl delphinidin trans-tonka-bean acetylation glucoside, the purities of which are sequentially 99.9%, 99.9%, 99.9%, 99.9%, 91.7%, 95.5%.