The relationship between autism spectrum disorder (ASD) and sexual offending (SO) is an overlooked issue, both in clinical practice and in research. Based on a pre-specified protocol (PROSPERO: CRD42024501598), we systematically searched Pubmed and Scopus, between January 1st, 1994 and January 12th, 2024, for articles related to SO in ASD. Study quality was assessed with study design-specific tools (Study Quality Assessment Tools, NHLBI, NIH). We found 19 relevant publications (five cross-sectional studies, two case-control studies, and 12 case reports). Seven of the studies were deemed of "good" quality, the rest as "fair". Included studies addressed three key aspects: 1) psychopathological characteristics of individuals with ASD that increase the risk of committing SO; 2) intervention strategies for individuals with ASD and SO; 3) involvement of individuals with ASD and SO in the justice system. Overall, while there is an increasing interest in this topic, more rigorous study designs, including randomised controlled trials, are needed to inform clinical practice and healthcare and social policies.