Abstract: Natural pigment extracted from phytolacca was applied to wool fabric. The effect of dye bath pH, dyeing temperature and the amount of pigment were analyzed. The adsorption mechanism of phytolacca pigment on wool fabric and fastness of dyed fabrics were also investigated. The results showed that K/S value of dyed wool fabric showed improvement with the increasing amount of phytolacca pigment. When the amount of pigment was more than 6%, K/S values almost remained the same. The K/S values decreased with the increasing of dye bath pH values. When pH was less than 3.5, the colour strength values were larger; when pH was higher than 4.5, the rate of pigment uptake was very low. It was found that while dyeing temperature was below 60 ℃, the color of dyed fabric was rose red, the dyed fabric was yellow when dyeing temperature exceeded 60 ℃. The washing fastmess of fabric dyed in low temperature was lower and was improved in high dyeing temperature.