Objective To observe the protective effect of growth differentiation factor 11(GDF11) on myocardial injury and the changes of myocardial apoptosis in type 2 diabetic C57BL/6J mice. Methods Sixty male C57BL/6J mice weighing 20-25 g were randomly divided into three groups:control group (control), type 2 diabetes mellitus group (DM) and GDF11 intervention group (DM + GDF11). To establish mouse model of type 2 diabetes, the mice were fed with high fat and high sugar diet for 4 weeks, and i.p. injected consecutively three times of streptozotocin (STZ) in a dose of 60 mg/kg. After the continuous high-fat and high-sugar diet for 4 weeks, the cardiac function was detected by small animal ultrasound, TUNEL staining was used to detect the apoptosis in myocardium, and the expressions of cleaved-caspase-3, Bcl-2, Bax were measured. Results Diabetic injury significantly reduced the left ventricular ejection fraction and left ventricular short axis shortening rate, and increased myocardial apoptosis. Recombinant GDF11 protein significantly improved cardiac function and reduced myocardial apoptosis. Conclusions Exogenous GDF11 can significantly reduce myocardial apoptosis and improve heart function after diabetic injury.