Background: Knowledge of prevention and removing the barriers of stigma and discrimination is a critical public health issue for HIV/AIDS prevention strategies in Nigeria. Objective: This paper is aimed at accessing the knowledge of HIV/AIDS prevention, causes and effects of stigma and discrimination towards people living with HIV/AIDS (PLWHA), among the final year dental students. Methodology: This was a descriptive cross-sectional study among final year dental students in accredited dental schools in Nigeria, 2016. At the time of conducting this study there were 8 accredited dental schools in Nigeria. Simple random sampling technique was used to pick four schools from the existing eight. All data obtained was analysed using IBM SPSS version 21.0. Results: Out of the 70 questionnaires administered 60 were filled and returned giving a response rate of 85.7%. Half (50.0%) of the respondents exhibited a good level of knowledge of HIV prevention. About two-thirds (66.7%) of the respondents exhibited good level of knowledge of HIV discrimination and stigma. The main cause of stigma against PLWHA was lack of knowledge about HIV (86.7%). The main effect of stigma on PLWHA as stated by 83.3% is that they hide their HIV status. Conclusion: The study showed that most final year dental students have good knowledge of HIV prevention; causes; and effects of stigma and discriminations among people living with HIV/AIDS. However, they need more training on how occupational HIV exposure should be handled in the clinic.