Studies on genetic variability, heritability and genetic advance were carried out with five genotypes of cowpea (Vigna unguiculata L. Walp) cultivated at two (rainforest and guinea savannah) agroecological environments. Analysis of variance revealed that though there was no significant interaction among the genotypes for most of the characters studied, they varied significantly for all the 16 characters at each of the two locations, indicating the existence of considerable variation for all the characters. Considerable amount of genotypic and phenotypic coefficient of variation was observed for all characters. High Heritability and genetic advance as per cent of mean were shown by clusters per plant, pods per plant, peduncle length, pod length, dry pod weight, hundred seed weight, seed per pod, number of seeds per plant and seed yield per plant indicating that these traits were controlled by additive genetic effects and could be dependable for grain improvement in cowpea.