The aim of this study was to assess the patterns and pattern disruptions of free radical processes in patients with obstructive jaundice of various origins, and the severity of jaundice before and after decompression. Oxidative stress markers were determined in 128 patients with obstructive jaundice with a tumor genesis (23.4%) or non-tumor genesis (76.6%). The patients were hospitalized at different stages of clinical signs of jaundice. We studied the anti-peroxide activity in plasma, basal and stimulated indicators of the chemiluminescence intensity in leukocytes, leukocyte activity coefficients reflecting the level of reactive oxygen species generated by leukocytes, malondialdehyde levels indicative of the degree of lipid peroxidation and cellular destruction, liver enzymes (markers of cytolysis) and bilirubin levels. Data for hepatocyte death and markers of oxidative stress correlated with the severity of jaundice, its duration and the method of its surgical correction. It is proposed that using markers of free radical processes to assess the prognosis and effectiveness of treatment and to personalize treatment measures will improve the results of jaundice treatment.