Cryptococcus neoformans is a fungus that primarily causes opportunistic infections in immunocompromised hosts. It can also cause various infections in immunocompetent patients. Pulmonary cryptococcosis involving the lymph node is relatively rare in immunocompetent patients. In this report, a previously healthy 17-year-old girl presented with high-grade fever and persistent cough. Chest X-ray and computed tomography (CT) scan revealed an anterior mediastinal conglomerate mass that expanded to the right supraclavicular area. Ultrasound-guided gun biopsy revealed histological evidence of cryptococcosis. Immunological screening tests did not identify immunodeficiency. She recovered completely with a combination therapy of amphotericin B and flucytosine for 2 weeks, followed by fluconazole for 8 months. The characteristics of cryptococcosis involving the mediastinal lymph node and the lung should be understood, and the possibility of cryptococcosis even in immunocompetent hosts should be considered.