The invention discloses a method for extracting and purifying anthocyanins from blueberry red leaves. The method is characterized in that two kinds of anthocyanins of which the content is close are contained in a blueberry red leaf anthocyanin extract and account for 93.9 to 99.0 percent of the content of the anthocyanins in the extract. The method comprises the following steps of: selecting fresh blueberry red leaves serving as raw materials, removing leaves which have plant diseases and insect pests and rotted leaves, cleaning by using clean water, drying under vacuum, crushing, sieving, extracting, concentrating under reduced pressure, purifying and separating by macroporous resin, concentrating under the reduced pressure, freeze-drying, saturating, dissolving, growing grains at low temperature, recrystallizing and the like to prepare a natural blueberry red leaf pigment product. By the method, the purity of the recrystallized anthocyanins is over 95 percent; and the anthocyanins are high in purity and simple in composition, and the method is low in production cost and high in popularization.