The simple chest X-ray study is essential in diagnosis of pulmonary tuberculosis, especially primary pulmonarytuberculosis. Authers analyzed the chest films and tuberculin tests of 521 cases which are suspected primarypulmonary tuberculosis coinically, from Jan. 1978 to Nov. 1982 at Seoul Red Cross Hospital. The results are asfollows; 1. Among the total 521 cases, the 115 cases of chst film reveal 245 probable pulmonary tuberculouslesions. 2. The coincidence of the parenchymal and lymphnodal involvement are observed in 40 cases (34.8%) with137 lesions(55.9%), parenchymal only in 23 cases (20.0%) with 25 lesions(10.2%) and lymphnodal only in 52 cases(45.2%) with 83 lesions(33.9%). 3. In observing the distribution of the 83 parenchymal lesions, the right lung istwo times as common as that of the left, being the highest in the RLL field with 41 lesions(49.4%), the lowest inthe LLL field with 3 lesions(3.6%). 4. In observing the distribution of the 162 lymphnodal lesions, there are 95lesions(58.6%) in the right and 67 lesions(41.4%) in the left, involving hilar nodes with 150 lesions(92.6%) andmediastinal nodes with 12 lesions(7.4%). The incidence of unilateral involvement is 13 cases (11.3%) and bilateral79 cases (68.7%). 5. Among the total 245 lesions, 141 lesions(57.9%) are smaller than rice in size, 120lesions(49.0%) are amophous in shape and 186 lesions(75.9%) are mainly calcific in density. According to theincrease of age, count and detection rate of the lesion on the chest film are increased. 6. Tuberculin testsshowed 26.1% negative rate in 115 tuberculous cases, and 51% positive rate in 406 negative chest cases.