In the human cell, genetic material is found in the nucleus (nuclear DNA) and in mitochondria (mitochondrial DNA). Although DNA is generally regarded as a stable chemical molecule, the role of external environmental factors (eg smoking) in causing DNA damage has not been fully elucidated. Νumerous researches have been done concerning the effects of smoking on various organs of the body (susceptibility to cerebral myocardium, peripheral angiopathy, chronic obstructive pulmonary disease, lung cancer etc.).The aim of the present brief review study is to examine the potential relationship between DNA damage and smoking. The study material included articles on the topic found in international databases, such as Google Scholar and PubMed, using the appropriate keywords: DNA damage, smoking, tobacco, oxidative stress, and a combination of these. As criteria for including the studies were used: a) studies of any date b) publication language: English or Greek. Criteria for excluding studies were: (a) studies in languages other than English (b) free announcements at meetings, written submissions to the publisher, and theses. It seems that smokers are more likely to have increased levels of DNA damage. However, additional well-designed research is needed to further clarify the relationship.