This study assesses the susceptibility of 31 legume varieties to Callosobruchus maculatus, a significant pest of these globally important, protein-rich staple crops, which are crucial for food security in sub-Saharan Africa. Field surveys and market visits across Northern Nigeria yielded 31 cowpea varieties, which were subsequently collected and evaluated for their susceptibility to Callosobruchus maculatus infestation. Physical attributes, including seed length, width, thickness, weight, density, volume, sphericity, porosity, surface area, and moisture content, were measured. The samples were then artificially infested with C. maculatus to assess resistance. Data analysis, including hierarchical data analysis, dendrogram clustering, histograms, and correlation analysis, was employed to reveal patterns and groupings of cowpea varieties based on physical traits. Distinct groupings of cowpea varieties emerged from the study, with smaller seed dimensions forming a cluster that included pigeon pea, Azuki beans, Achi Shiru, Farin Akidi, and Bakin Akidi. Another cluster, representing medium to large-seeded varieties, comprised 573-1-1, Kidney Beans, Shamjir Brown, and Zebra Beans. Overall, Farin Akidi exhibited the highest susceptibility to C. maculatus, followed by Agwugwu and Zebra Beans. In contrast, Lima Black, Lima Silver, and Kaki beans demonstrated the most substantial resistance. The study found negative correlations between pest resistance and seed traits, such as thickness, diameter, surface area, and weight, indicating their role in resistance. These findings provide valuable insights for breeders to develop more resilient cowpea varieties, thereby enhancing storage, adaptability, and genetic diversity, which supports global food security.