Sarcoidosis is a multisystemic disease of unknown etiology. Genetic factors play a considerable role in the onset of the disease. Tumor necrosis factor alpha (TNF-a) is a proinflammatory cytokine which plays an important role in the pathogenesis of the disease and the formation of granuloma by regulating cellular proliferation and apoptosis. The aim of this study was to investigate the role of TNF-alpha-308 G/A polymorphism in the development of sarcoidosis and to evaluate the association between the aforementioned type of polymorphism and the clinical course of the disease. Seventy patients with sarcoidosis and 50 healthy volunteers were genotyped for the TNF-alpha-308G/A polymorphism. Polymorphism variants were examined by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) on the DNA isolated from blood leukocytes. There were no significant differences in TNF-alpha-308A allele frequency distribution between sarcoidosis patients and the control group, but the TNF-alpha-308A allele was observed significantly more frequently in the sarcoidosis patients with Löfgren's syndrome when compared with non-Löfgren's patients. We have found that the TNF-alpha-308A variant is associated with Löfgren's syndrome in Serbian patients with sarcoidosis.