【Abstract】 ObjectiveTo explore the effects of interferon combined with chemotherapy on the clinical symptoms and immune function of patients with drug resistant tuberculosisMethods 80 patients with pulmonary tuberculosis were randomly divided into observation group and control group, 40 cases in each group. The control group was given conventional chemotherapy treatment. The observation group was given interferon therapy. The sputum negative conversion rate, focus absorption, the changes of immune function and clinical adverse reactions were observed. Results The observation group treatment effective rate (36/38,947%) was significantly higher than that of the control group (27/37,730%) (P<005). Compared with that before treatment, the sputum negative conversion and absorption of lesions were significantly improved, but those of the observation group more significantly improved than that of control group (P<005). CD3+, CD4+ and CD4+ /CD8+ after 6 months of treatment were significantly increased. CD8+ was significantly decreased (P<005). CD3+, CD4+ and CD4+ /CD8+ of observation group were significantly higher than that of control group (P<005). There was no significant difference of CD8+ between the two groups after the treatment (P>005). The incidence of adverse reactions of the two groups were not statistically significant (P>005). Conclusion The use of interferon combined with chemotherapy in the treatment of drug resistant tuberculosis can effectively improve the patient's sputum conversion and focus absorption, regulate immune function, improve clinical efficacy.