Diffuse pulmonary nodules have a wide range of causes as follows: 1, common such as exposure to dust, metal powder-related diffuse nodules; 2, diffuse nodules caused by infectious factors, such as cornual tuberculosis; 3, diffuse nodules caused by tumors, such as lung cancer, metastatic tumors, cancerous lymphangitis; 4, diffuse diseases related to connective tissue disease or vasculitis, with diffuse nodules in the lungs as the main manifestation; 5, granulomatous lesions, such as nodular disease manifestation diffuse nodules in the lungs.