Sarotherodon melanotheron (Rüppell, 1852, Cichlidae) is a species exploited by the local populations of the Ebrié lagoon. Morphometric measurements of all specimens of S. melanotheron caught in the heavily anthropized Biétry bay were used to study their growth. In S. melanotheron, the values of Lt and W fluctuated by 140 and 185.06 mm and 58 and 119 g, respectively. The allometry coefficient b was significantly different from 3 for the seize-weight relationship and from 1 for the seize-seize relationships. The allometry coefficient b was significantly different from 3 for the seize-weight relationship and from 1 for the seize-seize relationships. Therefore, growth was negative allometric for this species living on the coast and off the bay. Environmental factors linked to the pollution of the Bay of Biétry have influenced the growth of this fish species.