The reproductive biology of the West African ladyfish Elops lacerta Valenciennes, 1847 in the Gulf of Guinea was investigated. A total of 865 fish, 494 males and 371 females, were examined from January 2019 to December 2020. Specimens caught were mainly mature fish (83% of which 50.17% were mature males and 32.83% were mature females). Gametogenetic cycle of E. lacerta in the Gulf of Guinea started at the end of the cold season (CS). The spawning period began at the beginning of the warm season (WS), extended over the warm season (WS) with a resting phase observed between July and September. The maximum of the gonadosomatic index (GSI) preceding that of hepatosomatic index (HSI), showed that E. lacerta is a lean fish. Results showed that the overall sex ratio was in favour of male individuals. The size at first sexual maturity showed that males reached sexual maturity (26.6 cm of fork length) before females (30.1 cm of fork length). The mean absolute and relative fecundities were 82,979 ± 25,875 and 154 ± 34, respectively. Based on the reproductive biology, the information provided in this work could be helpful in the adequate management of this fish in the Gulf of Guinea. Further study should be conducted to investigate the role of hormones in regulating of Elops species spawning migration and gonad maturation.