Objective To explore the clinical value of procalcitonin in the diagnosis of tuberculosis (TB) patients. Methods The serum procalcitonin levels in 154 cases of treated tuberculosis patients and 30 healthy controls were measured by ELSA. Results The serum procalcitonin levels in active pulmonary tuberculosis patients were higher than that of the control group and the other tuberculosis group (P < 0.05). The serum procalcitonin levels in extra pulmonary tuberculosis patients group were higher than that of in control group and non-active pulmonary tuberculosis group (P< 0.05). The critical value of procalcitoninin diagnosis of active pulmonary tuberculosis was 0.15ng/mL. The diagnostic specificity and sensitivity were 81.2%, 76.9% respectively. The serum procalcitonin levels in patients with active pulmonary tuberculosis decreased significantly after treatment. Conclusion The serum procalcitonin levels could be used in the diagnosis of active pulmonary tuberculosis.