Fish and fisheries of Fosu Lagoon were surveyed when the lagoon was closed to the sea to assess its present status. Fish samples were obtained from hired local fishers using different fishing gears in each section of the lagoon. A total of 6,197 fish specimen comprising five species and four families were sampled as follows: Sarotherodon melanotheron (Cichlidae), Heterobranchus bidorsalis (Clariidae), Pellonula leonensis (Clupeidae) and Liza falcipinnis (Mugilidae). S. melanotheron constituted 99.5 % and 92.3 % of the total number and weight respectively of fish caught. The total length of S. melanotheron from all gears combined ranged from 4.1 cm to 14.0 cm while the weight ranged from 0.8 g to 47.3 g with a mean weight of 6.5 g indicating stunted growth. Catch rates of 0.94274 kg man h-1, 6.300 kg man h-1 and 0.255 kg man h-1 were estimated for cast net, drag net and gill net respectively with annual catch of 199 tones for the lagoon.