Background and Aim:In recent years, fast-food consumption has increased significantly among societies which is a consequence of many factors for example lifestyle changes. Undoubtedly knowledge and attitude of consumers are factors can influence on fast food consumption by individuals. So, goal of this research is study of knowledge and attitude of medical students about fast food consumption.

Materials and methods:This study was a cross-sectional study including 228 students of school of medicine of Shahid Beheshti University at medical science. The Samples were randomly selected from classes.The sample size was estimatedat 228 people. Basic science courses data were collected by using questionnaire determined its validity and reliability. Data were collected in November 2015. Collected data analyzed by descriptive statistics, chi2, T test, Mann–Whitney ,Kruskal–Wallis.

Result:Results of research showed 50% of students were women and 50 % were men. In this study 30/7 % of students never used fast food and 52/6 % of individuals were using fast food 1-2 times per week .The average score of knowledge of student was 8/22±2/22 and average score of attitude of student was 22/83±3/64. There was a correlation between knowledge and fast food consumption. (P=0/030) mean knowledge was 8/51±1/95 for women and 8/09±2/44 for men. There was no correlation between sex and knowledge to fast food consumption. (p =0/138 ) The mean score of attitude were in women and men 23/10±3/51 and 22/97±3/31 respectively. There was no correlation between sex and attitude to fast food consumption (p= 0/404 ) . 48/4% of students were in average level of knowledge to fast food consumption, 19/7% in weak level, 29/8% in good level and 2/2% in very weak level of knowledge. 68/4% of students had positive attitude to fast food consumption, 1/8% negative attitude and 29/8% had no opinion.

Conclusion:According to the high rate of fast food consumption between students and high tendency withless awareness of male students to fast food consumption, it is necessary to plan for informing students, especially boys.

Key words: knowledge, attitude, fast food, medical student, function