Abstract: The colour of mammalian skin is determined by many factors and mainly by the degree and distribution of melanin pigmentation. Tyrosinase is the key enzyme for melanin biosynthesis. Contact with different azo dyes is well known to produce contact dermatitis and some times depigmentation of the skin. In the present study we have reported the effect of known depigmenting dyes as well as some food, cosmetic and drug dyes on the activity of tyrosinase enzyme. The activity of the enzyme has been assessed in terms of oxidation of DOPA. The inhibitory effect of PPD was found to be maximum i.e., 85% while solvent yellow 3 and Brilliant crocin showed inhibition of 70 and 60%, respectively. The PPD and solvent yellow 3 were identified as noncompetitive inhibitors of tyrosinase by Linweaver Burk plot.