In view of the rising global death rate associated with inflammatory diseases, a cost-friendly, more effective and safer drug with lesser side effect is needed. The aim of this study was to evaluate membrane stabilization, albumin denaturation, protease inhibition and antioxidant activities as possible mechanisms for the anti-inflammatory effects observed in stem-bark of flavonoid-rich extract of Peltophorum pterocarpum (FREPP). The antioxidant activities were assessed using three various assays hydrogen peroxide, Nitric oxide (NO) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities. The mechanisms for the anti-inflammatory effect of FREPP was determined by membrane stabilization models, test of albumin denaturation, protease inhibitor assay, while the total flavonoid was examined using the aluminium chloride colorimetric test. The ability of FREPP to inhibit membrane lyses of RBC was used to evaluate the anti-inflammatory activity. At 0.1, 0.4, 0.8 mg/ml, FREPP inhibited hypotonicity-induced haemolysis by 61.03, 76.84 and 83.84% respectively. FREPP was effective in inhibiting albumin denaturation in a concentration dependent manner having the highest inhibition of 69.89% at 50µg/ml. Protease activity was significantly (P< 0.05) reduced across varying concentrations as against the control. It can be inferred from these results that FREPP has antioxidant and anti-inflammatory activities and the mechanisms of the activity may be attributed to its richness in flavonoids known to inhibit lysis of the membrane, albumin denaturation and protease activity.