The invention discloses a curtain and a manufacturing method thereof, and a projection system, and belongs to the technical field of display. The curtain comprises a first light-transmitting substrate, a black matrix, a photonic crystal layer and a second light-transmitting substrate, wherein the black matrix and the photonic crystal layer are arranged on one side of the first light-transmitting substrate; the photonic crystal layer comprises a plurality of photonic crystals which are arranged in a matrix shape; the plurality of photonic crystals comprise photonic crystals with at least two colors; the second light-transmitting substrate is arranged on one side, far away from the first light-transmitting substrate, of the photonic crystal layer. Through the photonic band gap characteristicof the photonic crystals, the curtain can filter out interference light rays, the contrast ratio of the reflected light rays is high and the display effect of images on the curtain is improved.