Lung nodules are different in nature, so the formation time of lung nodules will also be different, usually ranging from one week to several years, and the reasons for the formation of lung nodules mainly include inflammation, tuberculosis or tumors. 1. Tuberculosis: tuberculosis causes lung nodules mainly include two kinds, one is tuberculosis will form calcified foci after healing, the formation of lung nodules is to follow the course of the disease gradually transformed into calcified foci, the time ranges from a few months to a few years. The other type is formed during the active stage of TB, which may be formed within a week or a few weeks. 2. Inflammation:Lung nodules caused by inflammation may last from one week to several months, depending on the severity of the inflammation. 3. Tumors:Usually small nodules of unknown nature, irregular in shape, which may increase in diameter over months or remain unchanged for years. It is recommended to go to the regular hospital in time after checking out the lung nodules, and follow the doctor’s instructions to carry out the relevant examinations and treatments.