Legumes are plants with high nutritional values. It is necessary to control the nutritional quality of legumes at different stages of maturity for better popularization. This study aims to contribute to food security through determination of the phytochemical and antioxidant characteristics of the seeds of three legumes of the Canavalia genus according to their stage of maturity. Seeds of different stages collected in a field in the Gbèkê region served as biological material for this study. The seeds of three species at different stages of maturity: 30 days (S1), 40 days (S2), 50 days (S3), 60 days (S4) and 80 days (S5) after fertilization were collected and then dried in the sun and finally ground to obtain raw flour which was analyzed according to standard procedures. The results revealed that the contents of total phenolic compounds, flavonoids and tannins, suffered a decrease during seed maturation with the highest contents observed at the S1 stage. On the other hand, at the level of carotenoids, the peak was observed at stage S4 for all the seeds of the legumes studied. Overall, it appears that the best seed harvest stage for all the legumes studied is the S4 stage. This stage corresponds to the 60th day after fertilization of the flowers for species of the Canavalia genus. These seeds are potential sources of protein that can contribute to the fight against protein-energy deficiencies.