OBJECTIVE To investigate the characteristics and clinical value of serum tumor necrosis factor-alpha (TNF-alpha) and its receptor (sTNF-R), interleukin-1beta(IL-1beta) and its receptor(IL-1R), interleukin-6(IL-6) and its receptor(IL-6R) in patients with pulmonary tuberculosis, and to evaluate their role in the immunopathogenesis of tuberculosis. METHODS The serum levels of TNF-alpha, sTNF-R Iota IL-1beta,IL-1R, IL-6 and IL-6R were measured using the sandwich ABC-ELISA method in 41 cases of active tuberculosis, 21 cases of inactive tuberculosis and 20 normal controls. The serum levels of the cytokines in 17 cases of active tuberculos is were followed. RESULTS The serum levels of TNF-alpha sTNF-RIota IL-1beta,IL-1R, IL-6 IL-6R and the TNF-alpha/sTNF-RIota ratio were significantly higher in both the active and the inactive tuberculosis groups than those in normal controls (P <0.01 approximately 0.05). The TNF-alpha sTNF-R Iota IL-1 beta, IL-1R, IL-6 IL-6R levels and the TNF-alpha/sTNF-R Iota ratio in the active tuberculosis group were significantly higher than those in the inactive tuberculosis(P <0.01 approximately 0.05). The serum levels of TNF-alpha sTNF-R Iota, IL-1beta and IL-6 and the TNF-alpha,/sTNF-R Iota ratio were significantly lower in cavernous tuberculosis than those in non- cavernous tuberculosis (P < 0.01 approximately 0.05). After 2 months' antituberculosis treatment, the serum levels of TNF-alpha,sTNF-R Iota IL-1 beta, IL-1R,IL-6, IL-6R and the TNF-alpha/sTNF-R Iota ratio in 15(15/17) cases were significantly lower than those before treatment(P < 0.01 approximately 0.05). CONCLUSIONS TNF-alpha, IL-1 beta, IL-6 and their receptors may be involved in the immunopathogenesis of tuberculosis. Measuring the serum levels of proinflammatory cytokines and their receptors may be useful in evaluating the activity, the clinical pattern, and the prognosis of the disease and monitoring the clinical effect of antituberculous therapy.