Congenital heart disease is a congenital defect with a very high morbidity and mortality rate, of which Cyanotic Congenital Heart Disease (CCHD) is the most severe type.Due to the special anatomical changes of CCHD, the blood of the right ventricle cannot enter the pulmonary capillaries for full oxygenation, directly flows into the left ventricle and further flows into the systemic circulation, resulting in long-term hypoxia.Therefore, the study of the injury mechanism of cardiomyocytes under chronic hypoxia may provide a new treatment strategy for patients with cyanotic coronary heart disease.Mouse cardiomyocytes(CMCs) were treated with hypoxia for different periods of time (oh, 24h, 48h and 72h, respectively), followed by label free proteomic analysis.