Abstract: 1-butyl-3-methylimidazolium chloride ionic liquid which has a good solubility for wool keratin is used to improve the dyeability of wool fibers.The morphology and weak acid dye uptake rate of the wool fibers which had been subjected to ionic liquid treatment for different durations were investigated,and it was found that the scales of the treated wool fibers were eroded and their dyeability was improved considerably.The eroding degree of wool scales deepened and the dye uptake and dyeing rate improved as the time of treatment prolonged.Thus,modification of wool fibers using ionic liquid makes low temperature dyeing of wool possible.