Abstract: In order to improve the surface performance of yak hair fibers and enhance their dyeing property,the influence of low temperature plasma treatment of the yak hairs on their surface was studied.Scanning electron microscope(SEM) was used to analyze the morphological change of the fibers after treatment and investigated the tensile strength and dyeing property of the yak hair fibers treated by oxygen-plasma and air-plasma respectively.The results indicate that the surface scales of yak hairs are etched by the low temperature plasma treatment,and in the case of etching effect,air plasma is better than oxygen plasma.At the same time,plasma treatment has enhanced the dyeing rate and dye uptake of the yak fibers with the physical properties such as tensile strength remained.