We investigated incidence of pulmonary tuberculosis for 31 years (from 1960 to 1990) by sex and age among workers of NTT (Nippon telegraph and telephone corporation) in Tokyo area. Annual transition of recent years was mainly analyzed and following results were obtained. (1) Incidence in male of the twenties, thirties and forties decreased smoothly from 1960 to around 1980, then came to standstill and increase tendency was suspected, that is to say, 1) incidence in male of the twenties was minimum in 1976 (21 per 100,000 persons). Annual reduction rate (minus means decrease, plus means increase) from 1960 to 1976 was -11.7% and that from 1977 to 1990 was -0.4%. 2) incidence in male of the thirties was minimum in 1983 (0 per 100,000 persons). Annual reduction rate from 1960 to 1982 was -8.8% and that from 1984 to 1990 was +6.8%. 3) incidence in male of the forties was minimum in 1981 (0 per 100,000 persons). Annual reduction rate from 1960 to 1980 was -11.5% and that from 1982 to 1990 was +1.3%. (2) Incidence in male of the fifties decreased gradually from the 1960's and no tendency of increase was observed. (3) Incidence in female of the twenties, thirties and forties decreased almost continuously from 1960 to 1990 and no tendency of increase was observed in each age group, but total incidence in female (from the teens to the sixties) seemed to be leveling off after 1979. From these results, stagnant or increase tendency of pulmonary tuberculosis in young and middle-aged male was noticed.