A novel series of 2-substituted 4,5-diphenyl imidazoles were synthesized and investigated for their antioxidant activity and membrane stabilization activity. 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical assay was carried out to evaluate the antioxidant potential of the extract. The antioxidant activity of the synthesized compounds increased in a concentration dependent manner. In DPPH radical scavenging assay the IC50 value of the compounds ranged from 40 to 200µg/ml. The membrane stabilization activity of the compounds was evaluated using human red blood cells (HRBC) membrane stabilization method. The concentration of 88.88 to 444.44µg/ml showed a dose dependent inhibition of haemolysis of erythrocytes induced by hypotonic solution. Key words: DPPH, antioxidant, membrane stabilization