Sexual violence against children in sports receives little research attention. The aim of this Preferred Reporting Items for Systematic Reviews and Meta-Analyses-based systematic literature review was to synthesize the up-to-date knowledge and identify the already known and the still unknown information in this area. The literature search yielded seven eligible studies for inclusion. Their key outcomes suggest that sexual violence against children in sports is prevalent. Girls are more often the victims than boys, but gender appears to mediate the disclosure. Minority groups are at higher risk for sexual violence, and athletes at higher levels of competition seem to be more vulnerable for grooming. While the coach is often seen as the perpetrator, new research suggests that peer-athletes may precede the coach. Disclosure is a problem, due to personal and interpersonal concerns, which deters scholastic research in this area. In the final section of the review, a “what we know” and “what we need to know” list of highlights is offered as the concluding summary of the review. These factual points could raise the awareness of parents and/or guardians about the vulnerability of their children to sexual abuse if they are involved in sports. They could also attract the attention of the policy makers to the urgent need of developing and implementing preventive measures to make sports and exercise environments pleasurable and safe for children.