Abstract: The white croaker, Pennahia argentata (Houttuyn), is abundant in demersal fish assemblages in Ariake Sound and is a commercially important species. The reproductive biology of white croaker was studied by measurement of gonadosomatic indices (GSI) and histological examination of ovaries. Ovaries were classified into one of five maturity stages based on histological data: (1) immature/resting stage; (2) developing stage; (3) maturing stage; (4) ripe/spawning stage; (5) spent stage. The spawning season lasts from April to September but most activity is observed from May to August. Age at sexual maturity was assumed to be 1 year. Postovulatory follicles coexisted with yolk stage oocytes in histological sections of ovaries indicating that white croaker is a multiple spawner, spawning more than once in a single spawning season. Judging from the diel changes in the proportion of females with ovaries containing postovulatory follicles and oocytes at maturation stage, most females spawned in the evening between 19:00 and 21:30h. [Copyright &y& Elsevier]