SIRT3 is an important deacetylase in the mitochondria, and plays a critical role in coordinating multiple mitochondrial metabolism. With respect to its inhibition of tumor formation, SIRT3 protects normal cells from developing into tumor cells and tumorigenesis through against the reprogramming of tumor metabolism. SIRT3 regulates cells to intake the glucose, improves the ability of defending oxidation and the activities of oxidative phosphorylation complexes, promotes NADPH production and controls the production of energy. So SIRT3 indeed resists the reprogramming of tumor metabolism by multiple mitochondrial processes. This theory that SIRT3 can inhibit the reprogramming of tumor metabolism plays a guiding role in the early detection and treatment of clinical cancer, which will provide new strategies and methods for the treatment of cancer.