A seminal study was conducted in which the population dynamics (growth, mortality and recruitment) of the mudskipper (Periophthalmus papilio) in the Cross River, Nigeria, was elucidated for the first time using length frequency data and the ELEFAN software. The allometric relationship was: Weight = 0.012(Length)2.940, n = 415, r2 = 0.939, P <0.0005. The seasonalized Von Bertalanffy growth parameters were L∞ = 19.39 cm, K = 0.51 y-1, C = 0.3, and WP = 0.4. The instantaneous total mortality coefficient Z was 2.208 y-1 while the instantaneous natural mortality coefficient was 1.341 y-1. The instantaneous fishing mortality coefficient of 0.867 y-1 yielded the expectedly low exploitation rate E of 0.393. Our estimate shows that the species could reach an average maximum life span of about 6 years in the Cross River system. These results are used in quantitative elucidation of the state of exploitation of the population and will serve as input for the proper and scientific management of the fish resource.