Objective: To quantify the phenolic compound content and evaluate the anti inflammatory activity of Senna occidentalis extracts. Methodology: The quantification of phenolic compounds was carried out using UV-Visible chromatographic techniques. Anti-inflammatory activity was assessed through the erythrocyte membrane stabilization assay, employing human red blood cells as the cellular model. Results: The leaf extracts of S. occidentalis exhibited the highest content of phenolic compounds, with 219.596 mg GAE/100 g of total phenols, 35.470 g quercetin/100 g of flavonoids, 20.647 mg cyanidin-3-glucoside/100 g of anthocyanins, and 0.077 mg/100 g of catechins, compared to the fruit and stem extracts. Regarding anti-inflammatory activity, all extracts showed IC₅₀ values > 1000 µg/mL, indicating an absence of anti-inflammatory effect at the tested concentrations. Conclusion: The leaves of S...