Background and aim. Complete gonadal dysgenesis or Swyer syndrome is a rare genetic disorder characterized by 46,XY karyotype and female phenotype with undeveloped streak gonads and high malignancy risk. The condition usually manifests in teenage and young adults with delayed puberty and primary amenorrhea. The purpose of this study was to investigate the incidence and potential malignant outcomes of complete gonadal dysgenesis in Latvia. Methods. 37 patients were included in a retrospective study from 1996 to 2016.  In fifteen cases, additional patient information was available. Information from medical records was collected on age at the time of diagnosis: anamnesis data, laboratory results, histology of gonads, and treatment. Results. Complete gonadal dysgenesis with karyotype 46,XY was proven in 36 (97.3%) cases and one (2.7%) case with karyotype 47,XY,+21. The average age of patients at the time of diagnosis was 15.4 ± 8.0 years. The study included 15 cases: eight patients (53.3%) were investigated for primary amenorrhea, and incomplete development of secondary sexual characteristics, 5 patients (33.3%) with abdominal pain and lower abdominal mass, 2 patients (13.3%) were diagnosed at birth. Gonadectomy was performed in 12 cases (80%). The median time between diagnosis and gonadectomy was 0.4 ± 4.3 years. The histopathology results from the gonadal biopsy showed malignancy in 7 cases (58.3%). The most commonly diagnosed tumors were dysgerminoma and gonadoblastoma. Conclusion. Early diagnosis of Swyer syndrome is necessary in view of the risk of malignancy that can develop at a young age. In several cases, the diagnosis of the syndrome was made only after the malignant process development. The study showed the median time between diagnosis and gonadectomy was suboptimal. Therefore, women with amenorrhea and lack of secondary sexual characteristics require careful investigation.