CREST syndrome represents a form of scleroderma where the progressive autoimmune reaction is mainly manifested by the main symptoms, which make this acronym: calcinosis cutis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly and teleangiectasia. Among the first affected organs is the skin followed by the excessive fibrosis manifested by the deposition of collagen in dermis. Reactive oxygen species (ROS) theory has been underlined as one of the main pathogenetic mechanisms and triggering factor in development of scleroderma. The present study was aimed at estimating the marker of lipid peroxidation products (MDA) in plasma of patients with CREST syndrome having manifested symptoms of both Raynaud syndrome and positive ANA antibodies. The lipid peroxidation (MDA) level was significantly higher in the patients who had CREST syndrome and Raynaud syndrome for less than 10 years compared to the patients suffering from Raynoud syndrome for more than 10 years (p<0.05). Both groups were found to have a significant MDA level increase (p<0.001) compared to the control healthy subjects. In conclusion, the relationship between lipid peroxidation (MDA level) and Raynaud syndrome appearance may emphasize the role of ROS produced by the ischemia-reperfusion injury as an early pathogenetic mechanism in CREST scleroderma syndrome.