Androgen Insensitivity Syndrome (AIS) is a rare genetic condition affecting individuals with 46 XY genotypes. We present a case of Complete AIS (CAIS) in a 16-year-old phenotypically female patient with primary amenorrhea and bilateral inguinal masses. Despite male karyotype (46XY), physical examination and imaging revealed the absence of Müllerian structures and the presence of testes-like structures. The diagnosis was confirmed through hormone profiling and karyotyping. Management involved multidisciplinary collaboration, including surgical interventions (gonadectomy) and counseling. Early recognition and intervention in CAIS can mitigate psychological distress and optimize outcomes. This case also highlighted the importance of considering AIS in the differential diagnosis of primary amenorrhea, particularly in the presence of inguinal hernias.