A hydrocele of the canal of Nuck is an uncommon condition resulting from incomplete closure of a developmental structure in females. While more frequent in children, it can also appear in adults, where its nonspecific presentation as an inguinal swelling may complicate diagnosis. We report the case of a 36-year-old woman who presented with a painless, gradually enlarging swelling in the right inguinal region. Physical examination revealed a soft, fluctuant, non-reducible swelling confined to the inguinal canal. Imaging studies, including ultrasound, computed tomography, and magnetic resonance imaging, demonstrated a well-circumscribed, fluid-filled lesion consistent with a hydrocele of the canal of Nuck. The patient underwent a successful surgical excision, and a histopathological examination confirmed the diagnosis of a benign cystic lesion. She had an uneventful recovery with no recurrence at the six-month follow-up. This case emphasizes the need for heightened clinical awareness of hydrocele of the canal of Nuck, particularly in adult women presenting with inguinal swelling. Timely diagnosis and management can ensure excellent patient outcomes while avoiding unnecessary interventions.