This study was conducted to examine the antioxidant ability of carotenoids in the various membranes. It has been known that carotenoids are involved in peroxy-radical mediated peroxidation of phosphatidylcholine (PC) under atmospheric condition, and inhibited the chain propagation reaction of PC hydroperoxide (PC-OOH) formation. In case of rats liver microsomes and PC liposome, astxanthin was shown more antioxidant activity than beta-carotene, canthaxanthin. In case of human erythrocyte ghost membranes, significant antioxidant activity difference was not found among carotenoids. It was concluded that astxanthin have the ability to act as antioxidant on the peroxidation of membranes phospholipid in the biological membranes. Therefore hydroxy-group of carotenoids are inhibited more effective than oxo-group of carotenoids in preventing from biological membrane phospholipid peroxidation .