Diffuse pulmonary lymphangiomatosis (DPL) is a rare disease that is characterized by diffuse proliferation of abnormal pulmonary lymphatic channels. DPL occurs mostly in children and young adults and often undergoes a progressive clinical course, eventually causing deterioration of the lung. Both the clinical diagnosis and treatment of DPL remain a challenge. Here, we report a case of DPL in a 53-year-old Chinese woman with comprehensive investigations including pulmonary function tests, computer tomography (CT), bronchoscopy and histological examination of the lung biopsy, and review the literature.