Sertoli-Leydig cell tumors (SLCTs) are rare sex cord-stromal tumors, representing <0.5% of all ovarian tumors. We sought to describe prognostic factors, treatment and outcomes for individuals with ovarian SLCT. Individuals with SLCT were enrolled in the International Pleuropulmonary Blastoma/DICER1 Registry and/or the International Ovarian and Testicular Stromal Tumor Registry. Medical records were systematically abstracted, and pathology was centrally reviewed when available. In total, 191 participants with ovarian SLCT enrolled, with most (92%, 175/191) presenting with FIGO stage I disease. Germline DICER1 results were available for 156 patients; of these 58% had a pathogenic or likely pathogenic germline variant. Somatic (tumor) DICER1 testing showed RNase IIIb hotspot variants in 97% (88/91) of intermediately and poorly differentiated tumors. Adjuvant chemotherapy was administered in 40% (77/191) of cases, and among these, nearly all patients received platinum-based regimens (95%, 73/77), and 30% (23/77) received regimens that included an alkylating agent. Three-year recurrence-free survival for patients with stage IA tumors was 93.6% (95% CI: 88.2–99.3%) compared to 67.1% (95% CI: 55.2–81.6%) for all stage IC and 60.6% (95% CI: 40.3–91.0%) for stage II-IV (p < .001) tumors. Among patients with FIGO stage I tumors, those with mesenchymal heterologous elements treated with surgery alone were at higher risk for recurrence (HR: 74.18, 95% CI: 17.99–305.85). Most individuals with SLCT fare well, though specific risk factors such as mesenchymal heterologous elements are associated with poor prognosis. We also highlight the role of DICER1 surveillance in early detection of SLCT, facilitating stage IA resection. •Most (92%, 175/191) ovarian Sertoli-Leydig cell tumors (SLCTs) present as FIGO stage I disease with a favorable prognosis.•FIGO stage I tumors with mesenchymal heterologous elements are at higher risk for recurrence when not receiving chemotherapy.•Somatic (tumor) DICER1 RNase IIIb hotspot variants were found in 97% of intermediately and poorly differentiated SLCTs.•More than half (58%, 91/156) of individuals were found to have a germline DICER1 pathogenic/likely pathogenic variant.•DICER1 surveillance recommendations facilitated detection of asymptomatic ovarian SLCT with nearly all resected as stage IA.