Mitochondrial functions are altered in many human diseases including cancer. Development of mitochondria-targeted therapies, either through restoring normal mitochondrial function or promoting mitochondrial-induced cell death, is one of the attractive strategies to improve the outcome of cancer treatment. Recent advances have revealed the important functional involvement of mitochondrial dynamics in cancer biology. Dynamin-related protein 1 (Drp1), a member of the dynamin family of GTPases required for mitochondrial fission, has been found upregulated in certain types of cancers, such as lung and breast cancers. In addition, the roles of Drp1 in cell cycle progression, genome instability, cell migration and apoptosis in cancer cells have also been recently uncovered. These findings raise the possibility of targeting Drp1-mediated mitochondrial fission as an effective therapy for treating cancer. This article explores the function of Drp1 in cancer cells and discusses the theoretical basis for the development of potential targeted therapy.