A 19-year-old girl was referred with delayed puberty and ambiguous genitalia. She had short stature with high blood pressure and Turner’s stigmata with external genitalia Prader Score 4. Ultrasound revealed hypoplastic uterus with no gonad. Follicle stimulating hormone, luteinizing hormone and testosterone level were increased (51.29 mIU/mL, 23.66 mIU/mL and 742 ng/dl). Karyotyping revealed 46 XY with Fluorescence in situ hybridization cytogenetic study based on 300 cells showed mosaic chromosome, monosomy X (17%) and XY (83%). Laparascopic gonadectomy was done and showed that testes were only in the right inguinal canal. Then patient had external genitalia reconstruction and received estrogen replacement therapy. © 2023, Indonesian Society of Internal Medicine. All rights reserved.