Background: We reviewed and examined various financial incentives used in HIV prevention studies, and outlines important ethical considerations to using financial incentives in HIV prevention research. Methods: We searched PubMed using the terms “HIV”, “prevention”, and “incentive” for articles published between January 2009 and January 2013. Manuscripts were excluded if they were not written in English, not involving humans, and were not clinical trials. Results: Of the 84 manuscripts selected for review, 49 studies were conducted in the US, 13 were conducted in Africa, 17 in Asia, 3 in the Caribbean, 1 in Europe, and 1 in South America. Sample sizes ranged from 37 to 12,590. Of the 49 studies that offered financial incentives, the amount given ranged from $2.00 to $60.00 USD. We found a significant variety of monetary and non-monetary incentives used in HIV prevention studies. Several questions arose considering the ethical standards of using incentives. Conclusion: Incentives can be viewed as coercion of participants into harmful research protocols regardless of researchers obtaining informed consent due to the excessive nature of the incentive. Regulators of research should consider participants’ views when assuming that financial incentives diminish autonomy and capacity for informed decision making.