Studying urine ketoenolsubstances (KES) and the effects of vitamin B(12) and folic acid in the healthy and pulmonary tuberculosis cases, and the following results were obtained. 1. An increase in the urine KES was noted in the cases of moderately and far advanced pulmonary tuberculosis. 2. In the healthy and postoperative cases, the urine KES were increased from two hours after the administration of vitamin B(12), and from one hour after the administration of folic acid respectively. 3. These effects of vitamin B12 and folic acid were decreased in such order as minimal, moderately advanced and far advanced pulmonary tuberculosis. 4. Following the administration of folic acid, an increased precipitation was noted on the determination of the urine KES. This precipitation would be a source of error and might be a excretion of folic acid itself. 5. The effects of these vitamines were quite the same in the cases who had the breakfast with rice and soybean soup at the same time with the administration of vitamin B(12) or folic acid. 6. The effects of these vitamines were quite the same in the cases who had breakfast and vitamin B(12) or folic acid at the same time and also in the cases who had PAS-calcium later on. However, attention should be paid for the determination of the urine KES because of the precipitation due to PAS-calcium. 7. It was supposed that vitamin B(12) and folic acid did not have an effect upon dietary purine body metabolism, but promote general metabolisms and thus effect upon nucleic acid metabolism. Vitamin B12 and folic acid did not regulate the metabolism of KES which were excreted in the far advanced pulmonary tuberculosis cases.