Tobacco represents the single most preventable cause of disease and death in the world today. There were approximately three million deaths annually at the end of the 20th century and it has been estimated that the number of deaths will rise to more than 10 million by 2030.1 Globally, approximately 47% of males and 12% of females are smokers. In developing countries, 48% of males and 7% of females smoke. Whereas in developed countries, 42% of males and 24% of females smoke.2 Kuznar et al. believed that anti-tobacco prevention should be started very early before the age of 10 and continued up to the age of 21. Special attention should be taken at the age of 18 years as this time was found to be especially dangerous for the development of addiction.3 This report highlights the prevalence of smoking and factors associated with smoking among adolescents of Karachi, Pakistan. A crosssectional study was conducted on randomly selected 875 teenage male students from different schools, colleges and universities of the city. All participants were given informed consent forms (ICF) and 100% of them returned signed ICF. Their responses were anonymized for confidentiality reasons. Data was directly collected from respondents by trained interviewers. All the responses were scored on nominal and ordinal scales.