Objective To study autophagy as the protective mechanism of Zhenwu decotion in cardiomyocytes of rats with heart-yang deficiency. Methods After removal of the thyroid and intraperitoneal injection of doxorubicin, to establish the rat heart and kidney yang deficiency model, rats were administered with corresponding drugs for 10 days. We measured serum triiodothyronine (T₃), thyroxine (T₄), thyroid-stimulating hormone (TSH), and myocardial tissue BNP, LA, and CaN by ELISAs. LC3, ATG5, and P62 and protein expression was detected by western-blot. Inspected LC3 and P62 expression in rat myocardial tissue was examined by immunohistochemistry. ThePathological changes of myocardial tissue were observed by HE staining. Results Zhenwu decotion reduced the BNP content in myocardial tissue of rats with heart-yang deficiency-induced heart failure, increased the LA content in myocardial tissue, decreased the CaN content, increased LC3, ATG5, and BECLIN1 contents, and decreased the P62 content in myocardial tissue of rats with heart failure. Conclusions Zhenwu decotion improves the heart failure condition and energy metabolism of the heart. In the early stage of heart failure, the damaged cardiomyocytes protected by regulating autophagy.