Abstract: The goal of this study is to solve the problems encountered in the hydrogen peroxide bleaching of flax such as difficulty of obtaining the desired whiteness,and the toxic organic chloride AOX associated with the process,which is harmful to human body and the environment.Experiments of hydrogen peroxide bleaching of flax yarn with ACTIRON~ABO were performed and the process was optimized.The results indicated that adding of ACTIRON~ABO to the bleaching residual liquor can effectively accelerate the bleaching liquor to penetrate into the inside of the flax,at the same time the residual hydrogen peroxide in the bleaching liquor will further decompose,thus achieving the best bleaching effect of the flax yarn.This facilitates the improvement of the whiteness of flax yarn and protection of the environmental.