【Abstract】Objective To investigate the protective effect of chrysophanol on hypoxiainduced H9c2 injury in cardiomyocytes and its mechanism.Methods H9c2 cells cultured in vitro were divided into control group (normal culture), hypoxia group (hypoxia treatment) and 1,10,20 μ mol / L chrysophanol treatment group (1,10,20 μmol/L chrysophanol treatment, hypoxia treatment). LDH release in cell supernatant was detected by LDH kit, cell viability was detected by MTT assay, apoptosis was detected by flow cytometry, and the expression of bcl 2, Bax and cleaved caspase 3 protein was detected by Western blot.Results Compared with the control group, LDH release in the supernatant of hypoxic group significantly increased, cell survival rate and Bcl2/Bax level significantly decreased, apoptotic rate and expression of Cleaved caspase3 protein significantly increased (P＜005). Compared with the hypoxic group, 1μmol/L chrysophanol treatment had no significant effect on cells (P＞005). However, the above changes induced by hypoxia after 10 and 20μmol/L chrysophanol treatment were significantly improved (P＜005), and the effect of 20 micromol/L chrysophanol treatment group was significantly better than that of 10 μmol/L chrysophanol treatment group(P＜005).Conclusion Chrysophanol protects cardiomyocyte injury by antagonizing hypoxiainduced cardiomyocyte apoptosis.