Purpose <p>Although early psychosis and forensic mental health service use are well-studied concepts individually, less is known about their co-occurrence. We aimed to scope evidence on the overlap between early psychosis and forensic mental health service use, including evidence on forensic mental health service use within early psychosis groups and early psychosis cases within forensic mental health services. We further sought evidence specifically on prevalence or incidence, and associated risk factors and outcomes of forensic mental health service use in early psychosis.</p> Methods <p>We searched MEDLINE, EMBASE, CINAHL, PsycINFO, Scopus, Web of Science, Google Scholar, and thesis databases, with forward and backward citation searching. Eligible studies identified an early psychosis group and reported on forensic mental health service use.</p> Results <p>We included 74 sources, primarily European (47%) and cross-sectional (69%). Most examined homicide offenders with psychosis (62%), among whom a substantial proportion were early psychosis. Fewer studies examined broader forensic mental health service populations. Among studies on early psychosis populations (<i>n</i> = 5), two reported forensic hospitalization incidence (5%-6%), and three identified risk factors (male sex, Black-Caribbean race/ethnicity, and prior police contact). One study linked forensic hospitalization with greater inpatient service use over follow-up.</p> Conclusion <p>Although substantial evidence highlights an increased risk of committing homicide in early psychosis relative to chronic psychosis, evidence is limited on forensic mental health service use in early psychosis populations. Cohort studies using a broader mental health system perspective are needed to clarify the frequency, risk factors, and associated outcomes of forensic mental health service use in early psychosis.</p>