In vitro assessment of human erythrocyte membrane stabilisation activity of water extracts of Clitoria ternatea (Family: Fabaceae) roots, stem bark extracts of Stereospermum Suaveolens (Family: Bignoniaceae) and Oroxylum indicum (Family: Bignoniaceae), whole plants of Bacopa monnieri (Family: Plantaginaceae) and Alysicarpus vaginalis (Family: Fabaceae). Five different water extracts (600, 300. 150, 75, and 37.5 µg/ml) of each plant material were tested for human erythrocyte membrane stabilisation activity. The membrane stability activity of each plant material at different concentrations was measured spectrophotometrically at 540nm. Aspirin was used as the positive control and saline was used as the negative control. There was no in vitro human erythrocyte membrane stabilisation activity in the aqueous extracts of the plant materials used while aspirin at a concentration of 37.5µg/ml showed marked membrane stabilisation activity (25.45 ± 3.05 % inhibition). It is unlikely that anti inflammatory activities of C.ternatea, O.indicum, S. Suaveolens, B.monnieri and A.vaginalis are mediated via membrane stabilisation activity.