Walnut green husk pigment (WGHP),a natural plant dye,has poor coloring capacity,which limits its application.This study selected six natural plant polyphenols (gallic acid,tannic acid,ferulic acid,chlorogenic acid,ellagic acid and catechin) to study their effects on the dyeing properties of WGHP.Based on this,the kinetics model of synergistic dyeing of polyphenols and juglone (the main chromogenic substance of WGHP) were explored.Interaction among juglone,polyphenols and human hair keratin was clarified by molecular docking technology.The results showed that gallic acid,tannic acid,ferulic acid and chlorogenic acid contributed to the dyeing of WGHP,improved color fastness of hair,and did not damage the structure of hair scales.Compared with hair dyed by WGHP,the UV resistance and breaking strength of hair dyed by WGHP with four polyphenols reduced,but they were still higher than those of uncolored hair.In addition,the adsorption process of juglone on hair did not conform kinetic model,while after adding gallic acid,tannic acid,and ferulic acid,respectively,the adsorption process of juglone on hair conformed to the pseudo-second-order kinetic model.Furthermore,chlorogenic acid enhanced the intermolecular binding ability among juglone,polyphenols and human hair keratin,while tannic acid weakened the intermolecular binding ability.Gallic acid,ferulic acid and chlorogenic acid increased the total number of intermolecular hydrogen bonds.This study can provide a theoretical reference for the development of natural walnut green husk hair dye.