Incidence of abnormalities of sex chromosome is reported to be 1 in 448 new born babies. The association between clinical phenotype and sex chromosome abnormality is highly variable. A 34-year-old unmarried female patient reported to out patient department with complaints of primary amenorrhea and occasional pain in the lower abdomen. On examination, her height was 160 cm and body mass index (BMI) was 27 kg/m 2 . Breast development was Tanner stage 4, pubic hair was tanners stage 1 and no axillary hair was noted. Ultrasonography showed a hypoechoic structure in the place of uterus measuring around 1.7 × 1.1 × 1.0 cm and hypoechoic structures were also noted in relation to iliac vessels suggestive of gonads. Karyotyping showed 46 XY and 47 XXY mosaicism. Bilateral gonadectomy was done and histopathology showed testicular atrophy with Leydig cell hyperplasia. This case is reported in view of the interesting clinical presentation of this rare mosaicism.