Autophagy is the process of reusing the body's senescent and damaged cell components, which can be regarded as the cellular circulatory system. There are three distinct forms of autophagy: macro-Autophagy, micro-Autophagy, and chaperone-mediated autophagy. In the heart, autophagy is regulated mainly through mitophagy due to the metabolic changes of cardiomyocytes caused by ischemia and hypoxia. Myocardial remodeling is characterized by gradual heart enlargement, cardiac dysfunction, and extraordinary molecular changes. Cardiac remodeling after myocardial infarction is almost inevitable, which is the leading cause of heart failure. Autophagy has a protective effect on myocardial remodeling improvement. Autophagy can minimize cardiac remodeling by preventing misfolded protein accumulation and oxidative stress. This review summarizes the nestest molecular mechanisms of autophagy and myocardial remodeling, the protective effects, and the new target of autophagy medicine in cardiac remodeling. The future development and challenges of autophagy in heart disease are also summarized.