Cowpea [Vigna unguiculata (L.) Walp] seeds of cv. Pusa Komal were treated with mutagen viz., physical mutagen gamma rays (100, 200, 300, 400 and 500 Gy) and chemical mutagen ethyl methane sulphonate (0.25%. 0.30%, 0.35%, 0.40% and 0.45%). A systematic study was conducted in M1, M2 and M3 generations. In the M1 generation, germination, growth rate of root and shoot on 4th, 8th and 12th day after sowing, morphological abnormalities, pollen sterility per cent, survival per cent were highly effected by higher doses/concentration of mutagens. Germination percent decreased in general with increase in dose/concentration of mutagens. The inhibitory effect on these characters was more prominent with gamma rays than with EMS. Similarly, survival percent of plants decreased linearly with increase in the dose of mutagen. significant morphological variability was created among mutants using gamma rays and EMS which include abnormalities in growth habit, leaf, flower, pod and seed coat. The frequency of morphological abnormalities increased with increase in dose of gamma rays until 300 Gy followed by a decline in both the varieties. However, in chemical mutagen treated population, abnormalities increased until 0.30% followed by reduction.