Aimed at the problem of the hemp fiber injury use the chemical degumming, put forward the new method that the hemps pectin enzyme degumming and with the diagonal intersection trial method has defined the optimum technology that the pectin enzymes degumming namely effect time 2 h, gums enzyme: 5 g/L, pH value: 4.5, temperature: 50 ℃, After-treatment NaOH: 0.6％.