This study investigated the mutagenic tolerance of eight Bambara groundnut genotypes to Sodium azide (NaN3) using SDS-PAGE. The seeds of six genotypes; TVSu-86, TVSu-91, TVSu-186, TVSu-235, TVSu-242, TVSu-350 were collected from IITA and two landraces from Abia and Enugu local markets. The seeds were treated with five concentrations: 0.00%(control), 0.01%, 0.03%, 0.05% and 0.07% of NaN3 after pre-soaking for 6hrs in distilled water and sown in pots arranged in a Complete Randomized Design with three replicates. There was reduction in germination percentage and growth characters as concentrations of NaN3 increases. Early flowering was recorded at 37 days mutated with 0.07% of NaN3 compared to control which flowered late at 42 days. NaN3(0.07%) caused lethal effect on Abia and Enugu landraces. There was no significant (P>0.05) difference in yield traits among mutants and control. Mutant seeds significantly (P<0.05) increased protein content (19.12%) at 0.05% of NaN3 compared to control(18.5%). The number of seeds(0.99), seed yield(0.89) and pod yield(0.96) strongly correlated with seeds per pod (0.85). The SDS-PAGE revealed the presence of polypeptide bands in mutants compared to control. TVSu-235 and TVSu-350 genotypes had higher tolerance and yield traits to 0.01% concentration of NaN3, thus could be further improved in subsequent breeding.