In this study, HLA antigen distribution in active tuberculosis cases has been investigated to determine the relative risk of tuberculous infection in certain HLA antigen carrying persons. In 50 healthy persons of the same age group HLA-A, B, C antigen types were determined by using TERASAKI's microlymphotoxicity test. The results showed that HLA-BW 15 antigen confers the highest relative risk for tuberculous infection. Although the values are not very high our findings are in agreement with previously published results.