Background: AIDS is a sexually transmitted disease that can expose a person at risk with the onset of unprotected sexual behavior from adolescence. This study aimed to assess the misconceptions of HIV/AIDS, stigma in adolescents infected with AIDS and the perceived threats of HIV/AIDS in the Iranian college students. Methods: This cross sectional study was performed in Shahroud city, Iran. 1500 female and male students in the age bracket of 18-24 were included in the study. Multistage sampling was employed. After obtaining permission from the universities and stating the objective of the study, the questionnaires (HIV misconception, Stigma to HIVand PerceivedSusceptibility to HIV/AIDS) were distributed to students during the end of lecture time upon the agreement of the education officials and were then collected after 15 minutes. To ensure that the information provided remain confidential, students were asked not to write down their names and fields of study. Data were analyzed using SPSS software, version 20 and descriptive-analytical statistics, such as percentage, mean scores, t-test Spearman, and chi-squared and Pearson tests. Results: The results showed that 919 students (61.2%) were female and 539 students (36.1%) were male. The results of the present study indicated that there is false information and beliefs on AIDS among the Iranian adolescents and 592 students (40.7%) answered correctly. Considering the perceived threat of AIDS, the results indicated that in response to the item "unprotected sex put the adolescents at risk of sexual transmitted diseases" 416 (45.8%) female students and 321 (60.5%) male students answered totally opposite, indicating significant difference between the two genders (P=0.00). Conclusion: It is suggested to provide students with more information through mass media and discussions between students, teachers and parents. Training should increase the youth sensitivity to AIDS, as well as promoting sexual relationships until marriage or healthy and safe sex.