Uncontrol of the cell cycle with abnormal cell cycle phases is closely related to tumor development.Some cell cycle regulatory factors involve in the formation and development of tumors as oncogenes or tumor suppressor genes.Oral squamous cell carcinoma is the most common malignant tumor of the oral and maxillofacial regions，accounting for about 80%of the malignant tumor of these areas.Abnormalities of the cell cycle regulatory genes and over-expression of the gene products（proteins）are associated with the occurrence of oral cancer and its development process.With further study on the cancer cell cycle and its regulation mechanism，major progress will be made in the understanding of the cancer pathogenesis and new strategy for cancer treatment will be gradually developed.