The diffuse cystic lung diseases (DCLDs) are a pathophysiologically heterogeneous processes characterized by the presence of multiple thin-walled, air-filled spaces within the pulmonary parenchyma. The most common causes of DCLD are lymphangioleiomyomatosis (LAM) and pulmonary Langerhans cell histiocytosis (PLCH). DCLD develops rarely as a result of malignancy, typically secondary to metastases from peripheral sarcomas and mesenchymal tumors. DCLD have also been reported in a variety of other metastatic disease such as adenocarcinoma. Our case describes a patient with DCLD as a result of metastatic colorectal adenocarcinoma.