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An evaluation and morphometric seed studies were carried out in the screen-house of the College of Plant Science and Crop Production, and in the laboratory of Department of Plant Breeding and Seed Technology, FUNAAB respectively. Seeds of eight cowpea mutant genotypes were planted in plastic buckets filled with garden soil in the screen house, and arranged in a randomized complete block design with three replicates. Four buckets was assigned to each of the genotypes per replicate, to give a total of 96 buckets. Necessary cultural practices were carried out as required. Data were taken on both qualitative and quantitative traits for the screen-house study, these include; leaf colour, stem pigmentation, flower colour, plant height at six weeks, number of days to first flower and ripe pod, and seed related characters. Harvested seeds from the various genotypes were viewed using a digital morphometric seed reading metre to take various seed measurements such as, seed length, breadth, radius,circumference, testa length and seed angle. Data taken were analysed using analysis of variance (ANOVA) while their mean values were separated using Duncan’s Multiple Range Test (DMRT). Phenotypic variance along with its other components and heritability were also computed. The level of relatedness was carried out using correlation coefficient analysis. The cowpea genotypes showed varying degree of phenotypes; green, yellow foliage; pigmented versus non pigmented stem; white to white with purple winged petal and complete purple flower colour. Results of analysis of variance for both the agronomic and seed characters showed high significant differences existed among the mutant genotypes for all the traits studied. IF-BR-Cr was ealiest (53days) in maturing while, IB-Cyt.Y (unstable leaf form) was the last to mature (71days). The highest 100seed weight was recorded for Rosa-1 (26.7g), followed by IF-BR-Cr (16.6g), while Tvu 6198 had the least (9.6g). Seed length and angle ranged between 6.8mm – 9.74mm and 82.30º- 97.4º respectively. The following traits had both low phenotypic and genotypic variance, days to first ripe pod, pod length, testa length, seed length and breadth. High heritability was recorded for all the traits except seed radius (2.71mm) and angle (1.93º). A positive correlation was observed among the traits studied. Variation for quantitative and qualitative traits among the mutant genotypes could be attributed to their genetic background. The mutant traits could serve as marker gene during conventional breeding programme, also IF-Br-Cr which was early maturing and gave relatively good seed yield is recommended for multi-location trial to determine the influence of the mutant trait on agronomic traits. Morphometric analysis increases the confidence and accuracy of morphological classification and description of cowpeas.