The invention discloses a method for extracting coconut fiber. The method comprises the following steps: crushing coconut shell; adding deionized water and lipase into a cylinder, conducting uniform mixing, heating the mixture to 45 DEG C, and soaking the coconut shell into a cylinder for 2-3 h after soaking; adding sodium hydroxide solution in a cooking tank, putting the filtered coconut shell into the cooking tank, heating and pressurizing the mixture, cooking the mixture for 1-1.5 h, taking out the cooked coconut shell, and rinsing off the cooked coconut shell with water for 10-15 min; dissecting the rinsed coconut shell in the step (3) into crude fiber by a filament forming machine, and then rinsing the fiber with water for 10-15 minutes; mixing the deionized water with chlorine dioxide and sodium carbonate uniformly, and then the rinsed crude fiber in the step (4); conducting soaking for 30 to 40 minutes, taking out the fiber, and rinsing the fiber with hot water for 15 to 20 minutes; and dehydrating the dried fiber in the step (5), and then loosening the fiber with a carding machine to obtain the coconut fiber. The coconut shell fiber extracted by the method for extracting the coconut fiber of the invention has uniformity, less impurities, low residual fat ratio, and guaranteed quality.