The invention belongs to the field of tobacco processing, and in particular relates to a method for improving the quality of tobacco stems. The method comprises the steps of tobacco stem washing, ozone treatment, far-infrared irradiation, stem storage and the like, during which biological enzyme treatment is combined. By adopting ozone treatment, far-infrared radiation and enzymatic treatment with biological enzymes, this application makes full use of the internal changes of the tobacco stems after ozone, far-infrared radiation, and enzymatic hydrolysis, and better improves the internal quality of the tobacco stems. Specifically, this method can increase the content of total sugar and reducing sugar in tobacco stems, improve the softness of cigarettes, reduce the irritation of cigarettes, and reduce the tar content of smoke, thereby improving the internal quality of tobacco leaves. It has certain advantages in the production of cigarettes. promotion and application value.