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Photodegradation characteristics of selected natural dyestuffs were investigated on the basis of solar radiant energy. UVA and UVB fluorescent lamps were also applied to examine wavelength dependencies on the fading characteristics. The natural dyestuffs were observed to have poorer lightfastness in the comparison with AATCC Blue Wool L2. The order of fading susceptibility to solar radiation is as follows: Turmeric > Weld > Madder > L2. Moreover, it was concluded that the natural dyestuffs were strongly sensitive to visible light as well as to UV rays and L2 would be faded by visible light to a small extent. These results provide an important key to understanding the poor lightfastness of some natural dyestuffs.