Abstract: Background and Objective: Induced mutation is a valuable tool used by plant breeders for creating new variation where crop genetic diversity is insufficient. The study was conducted to select mutants that possess novel morpho-agronomic traits from M2 generation. Materials and Methods: Seeds obtained from M1 plants derived from gamma irradiated seeds of eight cowpea accessions were advanced to M2 generation. The M2 plants were screened and scored for mutant phenotypes on the field. Selected mutants were advanced to M3 and M4 generations to confirm their mutant phenotypes and genetic stability. Results: Observed mutation spectra and frequencies varied across all the accessions and radiation treatments. New cowpea mutants with novel phenotypic and agronomic traits were selected from five out of the eight accessions studied. The frequencies of yellow and white seedling (albino) mutants were higher than other mutants in all cowpea accessions and across radiation treatments. Mutation rates were higher (0.0057<1.745) in the four elite cultivars, whereas, lower range of mutation frequencies (0<0.4013) were recorded in Ife brown (IB) and its derivatives. The tall-erect non-branching trait of the mutant IB-ER could be introgressed to develop tall and erect varieties that may be useful for mechanized cowpea production. Conclusion: Mutants selected in this study could be of benefit for cowpea improvement, genetic analysis, biochemical and physiological studies.