TB mass screening for elementary and junior-high school pupils was revised in 2003 in Japan. Interview sheet with questionaires about past history of TB and BCG has been applied for all pupils to choose high risk groups for TB infection or TB diseases since 2003 April replacing previous mass-screening method with tuberculin test for first-grade pupils. We compare results of case-finding of school-children in 2001, 2002 and 2003 by the data of national TB surveillance system. Total number of latent TB infection (LTBI) subjected to preventive treatment decreased from 2920 (2001), 2173 (2002) to 1087 (2003). Number of LTBI detected by school mass-examination decreased markedly from 1310, 933 to 99. In addition, two peaks of LTBI in 6-7 years old and 12-13 years old children disappeared. Number of LTBI by contact examination gradually decreased from 881, 742 to 687. Number of LTBI detected by medical facilities also decreased from 199, 121 to 76. Total number of TB patients among school-children also decreased from 122, 72 to 46. TB patients found by school mass-examination showed a marked decrease from 23, 21, to 6. TB patients detected by medical facilities decreased from 68, 29 to 19. Number of TB cases detected by the contact examinations did not change. The reduction in the number of LTBI and disappearance of two peaks in 6-7 years old and 12-13 years old children are assumed to be mainly due to the revision of TB mass screening method in elementary and junior-high schools.