Abstract: In this article, According to the theory of the tryptophan reacted with the benzaldehyde derivative, 3,4- dihydroxy benzaldehyde was chemically reacted with the wool fabric under the acid condition, to achieve the coloration purpose. The results showed that the fastness of treated fabric was up to 4 grade or above. Meanwhile, the surface of fiber had not been changed, with the breaking strength not being affected, and the reacting time had been also reduced greatly. The optimal condition for wool coloration with non-dyestuff was: the concentration of 3,4- dihydroxy benzaldehyde solution and concentrated nitric acid 2.5% and 1.5% respectively, reacting temperature 70℃ and reacting time 2 min, bath ratio 1:25.