Sarcoidosis can cause fatal diffuse lung fibrosis in the end stage, so its early diagnosis and treatment can prevent the progression of fibrosis. Predominant ground glass opacity on high-resolution CT (HRCT) scans is a rare presentation of sarcoidosis. We report the case of a patient who presented with very few symptoms and signs of sarcoidosis; HRCT revealed large-scale ground glass opacity and minor lymphadenopathy. Bronchoalveolar lavage fluid contained turbid liquid. Sarcoidosis could be confirmed only based on pathological examination of the resected tissue. The patient was administrated prednisone at 40 mg/d orally with tapering of the dose. Lung HRCT scans taken 6 months after the prednisone treatment showed ablation of the ground glass opacity. This case report sheds light on an atypical HRCT presentation of sarcoidosis; the findings here will be useful for the early diagnosis of sarcoidosis and prevention of fatal complications.