The effect of alcohol alone on the oral mucosa and its association with the development of oral cancer is difficult to establish, principally because alcohol consumption histories are difficult to verify, alter over time, both with respect to beverage type and quantity, and are frequently confounded by tobacco use. This review considers the various pathways by which alcohol may exert such an influence. Namely, due to topical exposure (e.g. direct effect on cell membranes, altered cell permeability, variation in enzymes that metabolise alcohol) and/or systemic effects (e.g. nutritional deficiency, immunological deficiency, disturbed liver function). Finally, the numerous papers that have sought to establish the relative risk for oral cancer in association with alcohol intake are reviewed.