Abstract: HPLC was adopted to perform a quantitative research on the bonding of MCT reactive dye with silk fiber which was simulated by tyrosine,and their bonding mechanism was investigated.The bonding of reactive dye with tyrosine at different temperatures and different pH values was examined through testing the hydrolysate of the reactive dye and ionization chromatogram peak area of tyrosine. It shows that there is a linear relation between the hydrolyzing ratio of reactive dye and HPLC peak area.The reaction degree of reactive dyes with tyrosine is related with both ionization degree of tyrosine and non-hydrolyzed dyes.When pH value is 9.5,temperature is(85 ℃,)the strongest bonding between Reactive Red K-2BP and tyrosine is achieved.