The Acquired Immune Deficiency Syndrome (AIDS) is the expression of a spectrum of disorders caused by cellular and humeral immune dysfunction resulting from infection by human immune deficiency virus (HIV), since AIDS was recognized as distinct new disease entity in 1981, over 50 million individuals worldwide have been infected by HIV, of those more than 90% in developing world (Charles CJ et al.2001). According to estimates by the world health organization (WHO) and the Joint United Nation Program on HIV/AIDS UNAIDS) over 34 million people worldwide were infected with HIV in 2010 and about 42% were among young people (15-24years) (UNAIDS. 2010(a)),there are over 7,000 young people who become infected with HIV every day, more than five every minutes (UNAIDS.2009(a)).Young people are particularly vulnerable to the HIV pandemic(. Xiaodong Tan et al.2007), young people feel less susceptible to adverse outcomes associated with risk behaviors and are therefore at greater risk for HIV/AIDS(UNAIDS/WHO. 2005). The prevalence of HIV/AIDS in Iraq is low (less than 0.01 percent), 585 cumulative number of Iraqis & non Iraqis registered from 1986 – 2011 according to Ministry of Health/ Iraq ,the main mode of transmission of HIV in Iraq is contaminated blood with HIV (MOH. National AIDS Center.2012). Denial of the existence of AIDS and the tendency to regard it as a problem of others need to be counteracted, because although Iraq is a country with low HIV prevalence, conditions exist that could lead to the rapid spread of HIV/AIDS in the future such as poverty, social disparities, illiteracy, arrival of international community representatives (foreigners in general), and inadequate health care services are among the determinants that could lead to the rapid spread of the virus in the country . An important starting point for designing proper prevention tools is evaluation of how much people know about HIV/AIDS, especially among the educated persons and those who may be in contact with infected individuals and patients with AIDS(El-Nawawy AN.2008). University students in general are the most educated of the youths and their knowledge, attitudes, and practice (KAP) on health can be an indicator of the magnitude of the problem among youths (Namaitijiang M et al.2010). The United Nations has resolved that by 2010 at least 95% of young men and women aged 15–24 years should have access to the information, education and services necessary to develop the life skills required to reduce their vulnerability to HIV infection (UNGASS AIDS review.2006 ). In the literature, there are several studies, which assess knowledge and attitudes of the students towards HIV/AIDS. These studies were conducted in countries with different cultures and values(UNAIDS.2009(b)). In Iraq number of studies were done by Ministry of Health (Ali H.2006, MOH. National Aids Centre.2005, MOH. National Aids Centre.2008), Central Organization for Statistics and Information Technology (Central Organization for Statistics and Information Technology et al.2006 , Ministry of Education et al. 2001) and post-graduate students of Iraqi Scientific Counsel of Family and Community medicine(Al-Khazragy LA. 2002, Farhan SF.2006, Al.Bayati NA.2006), to assess knowledge and attitudes of people in Iraq towards AIDS patient among different target population .All these studies found alarming gaps in HIV and AIDS knowledge and negative attitudes towards people with HIV/AIDS . Countries are increasingly signaling the importance of equipping young people with knowledge and skills for making responsible choices in their lives, particularly in a context where they have greater exposure to sexually explicit material through the Internet and other media ( UNAIDS.2008). In countries where the spread of HIV/AIDS is subsiding or declining, such as Thailand and Uganda, it is primarily because young men and women are being given the knowledge, tools and services to adopt safe behaviors(UNAIDS .2002 ). In Iraq, there is no systematic and pragmatic AIDS education for college students, there have been few reports on knowledge, attitudes and behavior with regard to HIV/AIDS among Iraqi college students and although Iraqi adolescents have heard of AIDS, they are not familiar with the disease nor have they encountered people with HIV/AIDS, this situation may lead to unnecessary fear, ignorance and uncertainty among adolescents regarding this disease (Central Organization for Statistics and Information Technology.2004). Objectives of the study The current study attempts to: • Assess knowledge and attitudes of Iraqi medical and non-medical students attending 3rd and 4th study year in AL-Nahrain University regarding HIV and AIDS. Identify differences in HIV and AIDS knowledge and attitudes by gender, and college of students.