A Case Report of 46 XY Partial Gonadal Dysgenesis with Dual Gonadal Tumours 46XY gonadal dysgenesis is known as a disorder of sex development (DSD) that occurs due to abnormality in gonadal development. There is a conflict between one’s genotype, phenotype, and gonadal development, which influences the wide range of presentation and clinical appearance of 46XY females. This was a case of a 46XY female who presented with primary amenorrhea with delayed puberty at the age of 18 years old. She had ambiguous genitalia. Her breast and pubic hair were at Tanner Stage 2. Transabdominal ultrasound found a small uterus with a vagina; however, the gonads were not seen. A magnetic resonance imaging (MRI) showed a 20mm right gonad located extra-pelvis near the right iliac vessels while the 9mm streak left gonad was at the usual location next to the sigmoid colon. All her tumour markers were normal except lactate dehydrogenase (LDH) was elevated. She was given estrogen therapy for pubertal induction and underwent laparoscopy prophylactic bilateral gonadectomy. The intraoperative findings were similar to the MRI findings, and the histopathology examination (HPE) results showed left gonadoblastoma and right dysgerminoma FIGO stage 1A. She continued taking estrogen therapy until she had withdrawal bleeding, and oral progesterone was added. 46XY-DSD has high risk of developing germ cell tumour and requires prophylactic gonadectomy as soon as the diagnosis is established. However, delay in presentation and surgery may affect the outcomes and prognosis.