Tobacco is either chewed or smoked; it is equally harmful in both forms and there is no safe way to use the tobacco. Use of tobacco is now emerging as one of the major factors responsible for premature deaths in India. Comet assay is performed under alkali conditions and it can estimate damage in a single cell. The result of the present study indicates the greatest amount of damage in tobacco chewers as compared to controls. Comet assay is a valuable tool to assess the DNA damage.