Alcohol dependence syndrome is defined as a cluster of physiological, behavioural and cognitive phenomena in which the use of a psychoactive substance takes on a much higher priority for a given individual than other behaviours that once had greater value. In European Union the problem of the addiction affects about 5% of men and 1% of women each year. Long lasting alcohol abuse is detrimental to the whole body, including the oral cavity. The observable changes are usually caused by a convergent impact of a number of factors. The changes differ depending on the chemical features of the consumed substance, the life style adopted - as a consequence of the addiction, simultaneous addiction to nicotine, and finally on the medical treatment applied at different stages of the disease. Pathological changes may occur in all structures in oral cavity (teeth, periodontium, tongue, mucose membrane and salivary glands). Individuals addicted to alcohol revealed high percentage of carious losses and chemical damage enamel and dentine and inflammatory changes of the periapical area of teeth. Presence of these changes is linked unfortunately with low indicator of treatment. There is independence between alcohol addiction and damage of periodontium (clinical attachment level and pocket depth). Results of alcohol abuse may be also double-sided, painless, noninflammatory and non-malignant swelling on salivary glands (sialosis). Alcohol is said to be the risk factor for development of flat-epithelial cancer of the oral cavity. The most frequent localization of cancerous changes is the bottom of the oral cavity and the side of the tongue.