INTRODUCTION: To understand groups at higher risk to engage in HIV Risk Behaviors is one of the main ways to prevent HIV. Because adverse life events (ACEs) are related to epigenetic changes impairing cognition and increasing the likelihood of risk behaviors, the aim of this work was to systematically review studies investigating ACEs effects in HIV Risk Behaviors. METHOD: Searches combining terms about ACE and HIV Risk Behaviors were done in PubMed, Web of Science and Embase. Original papers assessing a group of individuals with ACE and individuals with no ACE and comparing them about the frequency of HIV Risk Behavior (i.e., infrequent condom use, multiple sexual partners and intravenous drug use) were included. Data on each study was assessed and results were considered for any ACE and other types of ACE more often reported. Methods were also reviewed. When it was possible meta-analysis were made for each HIV Risk Behavior assessed for any ACE and for sexual and physical abuses. RESULTS: Nine studies were included. For any ACE and any HIV Risk Behavior five papers studied this relation with two finding a significant positive relation between those variables, for infrequent condom use two studies found a significant positive relation, for multiple sex partners one study found a significant relation, a meta-analysis between any ACE and multiple sex partners were significant and positive. For sexual abuse, seven papers studied the relation with HIV Risk Behaviors. Two studies found a significant relation for infrequent condom use, with a meta-analysis appointing a significant relation, for multiple sex partners, no study found a significant relation, neither the meta-analysis. For physical abuse, five papers studied this relation with HIV Risk Behaviors. One study found a significant relation for infrequent condom use, and one study found a relation for multiple sex partners, with a meta-analysis showing a significant relation between those variables. For intravenous drug use we could not draw any conclusions due to the low number of studies assessing this HIV Risk Behavior. DISCUSSION: This review indicated that there is some evidence suggesting ACE effects in HIV Risk Behaviors, but robustness lack of consistency due to the small number of studies and variability in methods. More strong data can support future preventive directions focusing on people who passed by ACEs.