The invention discloses a method for improving Al0.3CoCrFeNi high-entropy alloy intensity. Five kinds of analytical pure metals of Al, Co, Cr, Fe and Ni are blended according to the atomic ratio of 0.3 to 1 to 1 to 1 to 1, smelting is carried out in a vacuum arc melting furnace, the molten alloy is subjected to suction casting to form plate-shaped high-entropy alloy materials with 2mm thickness, 10mm width and 85mm length, and then a high-entropy alloy is subjected to cold rolling and annealing heat treatment to eliminate the residual internal stress, generated in the casting process, of the high-entropy alloy; and then a wire cutting machine is used for cutting bone-shaped standard tensile samples with a standard distance of 5mm, the front faces and back faces and the two side faces of the tensile samples are polished, and the polished samples are subjected to a double-glow chromizing test by using a double-glow metal furnace, and finally, the obtained samples are strengthened high-entropy alloy samples. According to the method for improving the Al0.3CoCrFeNi high-entropy alloy intensity, through a double-glow chromizing technology, the friction coefficient of the high-entropy alloy is reduced, and the amplitude is greatly reduced.