Mitochondrial dynamics is the dynamic balance process in which mitochondria continuously divide and fuse under physiological or stimulating conditions, thereby regulating the distribution, quantity, size and shape of mitochondria in the cell. In cells, the regulation of mitochondrial dynamics is closely related to the functions of mitochondria, which include providing energy, regulating calcium homeostasis, participating in programmed cell death, cell signal transduction, and cell metabolism. In cancer, mitochondrial dynamic regulation is closely related to the proliferation, migration, treatment and drug resistance of tumor cells. Therefore, mitochondrial dynamic regulation has become a research hotspot in the field of cancer, and has shown great potential in tumor therapy. In this review, we review the key features that mediate mitochondrial dynamic regulation, and discuss the mechanisms involved in tumorigenesis and development and its potential in tumor therapy.