Ankylosing spondylitis (AS) is a chronic inflammatory disorder characterized by inflammation of axial skeleton and enthesopathies. Tumor necrosis factor inhibitors (TNFi) shows good clinical responses in the AS patients who don`t have good response to non-steroidal anti-inflammatory drugs. Although TNFi are relatively safe for AS patients, serious infections, including tuberculosis and fungal infection, could develop. Here, we reported a first Korean experience of pulmonary cryptococcosis in a patient with AS treated with etanercept. A 64-year-old man visited with a newly developed lung nodule revealed in the chest radiography. He was diagnosed as having AS and administered with etanercept for 5 months. Histopathology of the lung nodule revealed pulmonary cryptococcosis. There was no evidence of CNS involvement, so he was treated with oral fluconazole. After 7 months, the follow-up chest CT showed improvement of the pulmonary cryptococcosis.