Lipid peroxidation is a complex process which is initiated by abstraction of hydrogen atoms from unsaturated fatty acids of phospholipid and lipoprotein complexes yielding conjugated dienes. The conjugated dienes then react with molecular oxygen to produce peroxy radicals which propagate the chain reaction by abstracting hydrogen from other unsaturated Iipids. Some antioxidant defenses are located both in extracellular and intracellular compartments. Because our endogenous antioxidant defenses are not completely effective, dietary antioxidants are of particular importance in diminishing the cumulative effects of oxidative damage. Spices have a key role as chemopreventers in human diet . Effect of spice principles on scavenging of superoxide an ion had been earlier investigated. Tunnerin, a water soluble antioxidant peptide from turmeric was studied for its protective effect against reactive oxygen species induced lipid peroxide-mediated membrane and DNA damage. Breakdown of lipid hydroperoxides and endoperoxides lead to the formation of more than twenty known products of lipid peroxidation. The estimation of the end product assayed as thiobarbituric acid reactive substances (TBARS) is a measure of lipid peroxidation. Free radical intermediates have been linked to clinically important disturbances like ischemic heart diseases and atherogenesis. Aruna et al. have reported the effect of cumin turmeric, ajwain pepper, aniseed, curry leaves, coriander seeds, fenugreek seeds and ginger as cancer protective agents. But no detailed investigations were carried out on the antioxidant effect of the spices. Since coriander forms one of the commonly used spices, we have studied the role of coriander seeds on lipid peroxidation and antioxidant defense mechanisms in rats given high fat cholesterol diet.