It is possible for tuberculosis balls to be misdiagnosed as lung cancer. In many cases, it is necessary to distinguish between the two diseases through bacteriologic tests and pathologic findings of lung lesions. Tuberculosis is an inflammatory disease of the lungs that develops as a result of infection by the tubercle bacillus, whereas lung cancer is a malignant disease that develops as a result of a number of factors, including smoking. The nature of the two diseases is completely different, but there are similarities between the two diseases in terms of clinical manifestations and chest CT examinations, for example, both of them have symptoms such as coughing, coughing up sputum, fever, etc., and both of them are manifested as nodular foci in the lungs in chest CT. In patients with tuberculosis ball, tubercle bacilli are found in sputum, and in patients with lung cancer, the nature of the lesions is clarified through biopsy and pathologic examination, so that tuberculosis ball will not be misdiagnosed as lung cancer in general.