To study and compare the attitudes, concerns, perceived impact and coping strategies for avian influenza (AI) among the first year medical students (FYMS) and interns in Tehran University of Medical Sciences. This was a cross sectional study carried out on FYMS (n=158) and interns (n=158) in 2008. The data collection tool was a questionnaire containing 37 questions in five parts. The three choices including "agree, disagree and unsure" were considered for all questions. We used Chi-square and Fisherʹs exact tests for analysis. Most of FYMS and interns (78.2%) believed their health would be depended on the care of their selves. Most of them (95.3%) believed that if they knew avian flu better, they could be more prepared for it. The majority were concerned about risk to their health from their work (62.7%). Most (67.7%) accepted the risk and only 5 (1.6%) would consider stopping work. For non-work concerns, 70.9% were concerned about their spouses/sexual partners and 65.8% about their children. For perceived impact, most (66.5%) believed that they would feel stressed at work and the majority (74.4%) expected an increased workload. FYMS and interns have positive attitudes but major concerns about contracting AI and its relation to medical practice.