RESUMO
To assess and compare knowledge, attitudes and practice regarding tobacco use of college students in Iran, US and Chain. A modified questionnaire used in each of country US, Chain and Iran. A total of 3089 usable surveys were collected [47.5% for male and 52.5% for female]. Both descriptive and inferential statistical tests were employed in data analysis. Compared to male participants, American's female and male students scored higher in knowledge, Iranian genders [both female and male] students scored higher in negative attitude scale of the questionnaire regarding tobacco use. Knowledge of female students was a little greater than male students and their attitude was more negative. Male respondents also were more likely to smoke cigarettes and use other tobacco products and in heavier quantities. The findings provide exploratory information about aspects of tobacco use among students [as an important and reference class of the Iranian society], and based on the results, recommendations are made to national health policy makers and health educators for reducing tobacco related risks through improving associated knowledge, attitude and practice