Aims: Senna obtusifolia (L.) is an important wild herbaceous species for subsaharan Africa population. It is used in human food and traditional medicine to treat several deseases. In Burkina Faso, despite its potentialities, this species is of a little interest in scientific research. The aim of this study is to provide a good knowledge of the genetic diversity of this species. Study Design: The experimental design used was a randomized Fischer block type with three replications. Place and Duration of the Study: The study was carried out at Gampéla during 2018 rainy season. Methodology: Seventy (70) accessions of Senna obtusifolia were used for the evaluation of agromorphological variability. A total of twenty-seven (27) quantitative traits were studied. Results: The study revealed the existence of a great variability within the studied collection. Among the twenty-one (21) traits used for the analysis of variance (ANOVA), seventeen (17) variables significantly discriminate the accessions. A high heterogeneity was observed for the number of leaflets of the three first leaves and the number of floral pieces. In addition, significant correlations were observed between several variables. Indeed, the number of primary branches was positively correlated with the number of fruits per plant (r = 0.483), the number of grains per plant (r = 0.352) and the leaves biomass (r = 0.279). However, the number of days at flowering (NJF) is negatively correlated with the number of primary branches (r = -0.281). The variability obtained was structured in three groups. The third group is composed of accessions with the best agronomic performance that could be used in future breeding program. Conclusion: A high agromorphological diversity of Senna obtusifolia was observed and could be used in a breeding program.