The results of a study conducted on Trichiurus lepturus during 1967-70 and supplemented by observations made during 1986-87 are presented in this paper. Majority of males attain maturity at 42 cm and the females at 46 cm length.  Spawning is prolonged and takes place during January-August period. The individual fish spawns atleast twice during the spawning season. Fecundity varied from 2,380 ova in 42 cm fish to 27,320 ova in 77 cm fish. The annual sex ratio indicated that males outnumbered females in all the years. The sex ratio in relation to the length of fish showed that males dominated between 26-70 cm, the proportion of males and females was equal at 74 cm, females outnumbered between 78 to 94 cm and all the fish were females beyond the 94 cm length group.