Circadian clock genes,which are a group of genes that control and maintain the running of the circadian rhythms, exhibit rhythmic expression under constant light-dark cycles through a series of transcription-translation feedback loops, thereby maintaining normal physiological and biochemical homeostasis in the human body and participating in the onset and progression of diseases. Oral cancer is a malignant tumor originating from the oral mucosa, with an increasing incidence rate each year, closely associated with adverse lifestyle habits and environmental factors. Studies have shown that abnormal expression of circadian clock genes can affect the occurrence and development of oral cancer through various mechanisms. In this review, we summarize the mechanisms by which circadian clock genes affect the onset and progression of oral cancer, including their roles in the cell cycle, autophagy, immune microenvironment, and epigenetics, with the aim of providing a theoretical basis and new insights for the precise prevention and treatment of oral cancer.