Pulmonary occupancy is not necessarily lung cancer, but many other diseases can also cause pulmonary occupancy, and further examination is needed to clarify the nature of the patient. Pulmonary occupancy refers to nodules or solid masses in the lungs. In addition to cancer, diseases such as tuberculosis, Wegener’s granulomatosis, and fungal infections can also have pulmonary occupancy. Pulmonary occupancy is a characteristic of imaging description, and imaging doctors usually use the description of occupancy when considering lung tumor, but the occupancy described by imaging may not be 100% tumor, and it should be combined with other tests, such as lung puncture biopsy, bronchoscopy or transbronchoscopic lung biopsy, sputum exfoliation cell examination, through which a definite diagnosis can be made. When a patient has a lung occupancy, the chance of developing cancer is actually not high in general. Patients should maintain an optimistic state of mind and actively cooperate with the above examinations, and should not be pessimistic and delay treatment.