Aim: to investigate and stratify the structure of comorbidity of patients afflicted with choledocholithiasis with concurrent mechanical jaundice, to highlight bidirectional relationships between cholelithiasis and concomitant diseases, including metabolic, cardiovascular, gastrointestinal and cardiac disorders, thus characterizing common risk factors, pathophysiological mechanisms and genetic morbidity, and evaluating the influence of accompanying nosology on treatment strategy. Object and research methods. In the period from 2019 to 2023, we conducted a study evaluating the presence and structure of concomitant pathology afflicting patients with choledocholithiasis complicated by mechanical jaundice in the surgical department No. 2 of the Kyiv City Clinical Hospital of Emergency Care. 297 patients participated in the study. The mean age of participants was 59.2 years, males 41.07%, females — 59.93%. The results. The results of the revealed comorbidity were stratified by condition severity and three age groups — 18 to 39, 40 to 59, and >60 years. The influence of comorbidities on the surgical treatment of choledocholithiasis complicated by mechanical jaundice was characterized in accordance with the 2018 Tokyo Clinical Guidelines for the Treatment of Acute Cholangitis and Acute Cholecystitis taking into account the Charlson Comorbidity Index and the American Society of Anesthesiologists physical status classification system. The role of these indicators in preoperative risk assessment, surgical decision-making and prediction of postoperative results were outlined.