A study on the maturity stages revealed that the mud crab Scylla tranquebarica is a continuous breeder. Mature and spent stages were found to occur almost throughout the year. The berried females were encountered throughout the year with peak availability during December - February. The male matures on attaining a carapace width of 110-120mm and female 120-130 mm. The breeding cycle has been studied for one year (August 2000 to July 2001). Sex ratio indicated that the females out numbered the males.