Fuente: WIPO "hemp" The invention provides a composite modification method of high-adsorbability China-hemp fiber, which comprises the following steps: firstly, treating the China-hemp fiber by using 3-chloro-2-hydroxypropyl trimethyl ammonium chloride in an alkaline environment, and enabling the fiber surface to carry positive charges by using a chemical reaction between the 3-chloro-2-hydroxypropyl trimethyl ammonium chloride and the fiber of the China-hemp fiber; secondly, positive charges are generated after chemical reaction of the fibers, so that the stability of the charges on the fibers is improved, and the modification effect is ensured; then, a magnesium chloride solution is used for secondary modification, magnesium hydroxide is formed on the surface of the fiber, and the adsorbability of the fiber to the dye is further improved. Through the mode, the composite modification method of the high-adsorbability China hemp fiber, which is green, simple and high in dye adsorbability, is provided.