A method for modifying a non-woven fabric of chitosan fiber. The method includes: adding succinic anhydride to an industrial alcohol, ethanol, or acetone controlling the mass ratio of succinic anhydride to the non-woven fabric at between 0.8 and 3.5 and stirring the resulting mixture until the succinic anhydride has dissolved to yield a succinic anhydride mixed solution placing the succinic anhydride mixed solution in a constant temperature shaking bath heating the succinic anhydride mixed solution adding an HCl solution to the succinic anhydride mixed solution, and stirring evenly to yield a HCl mixed solution immersing the non-woven fabric in the HCl mixed solution dehydrating immersing the non-woven fabric in ethanol or acetone immersing the non-woven fabric in anhydrous ethanol or pure acetone dehydrating and air drying the non-woven fabric.
