To provide a method for enhancing an antioxidant substance content of a plant.SOLUTION: A method comprises (a) arrangement of at least one light transmissive material for adjusting or holding light transmittance of a wavelength between a light source and a photoreceptor of a plant； (b) adjustment of at least two wavelength areas, out of, when the light emitted from the light source passes the light transmissive material, the light transmissive material makes light transmittance of 340-500 nm area lower than 65%, the light transmissive material makes light transmittance of 500-600 nm area lower than 60%, and the light transmissive material makes light transmittance of 600-850 nm area lower than 83%.SELECTED DRAWING: Figure 3【課題】植物の抗酸化物質含量を高める方法を提供する。【解決手段】（ａ）波長の光線透過率を調整または保持する少なくとも１つの光透過性材料を、光源と植物の光受容体との間に配置することと；（ｂ）該光源が発する光が該光透過性材料を通過すると、該光透過性材料が、３４０ｎｍ～５００ｎｍ領域の光線透過率を６５％より低くする；５００ｎｍ～６００ｎｍ領域の光線透過率を６０％より低くする；および６００ｎｍ～８５０ｎｍ領域の光線透過率を８３％より低くする；のうち、少なくとも２つの波長領域を調整することとを含む。【選択図】図３
