The severity of multiple nodules in the lungs depends first of all on the size of the nodules. If the nodules are all less than 8 mm in diameter, regular review of chest CT is usually sufficient. However, if the nodules are larger, the exact severity will depend on the nature of the nodules, the cause of the disease, and the effectiveness of the treatment. Multiple nodules in the lungs are most commonly caused by infectious diseases, such as bacteria, fungi, viruses, parasites, tuberculosis, etc. The disease is more serious at this time, and if not treated in a timely manner, it can easily lead to the spread of infection and the formation of serious complications and sequelae, but such diseases can be cured by anti-sensitivity treatment. In addition, it is important to focus on excluding the possibility of tumors, because malignant tumors are quite serious diseases, patients have poor prognosis and their survival period is mostly shortened significantly, such as lung cancer, metastases, lymphoma, etc. Benign tumors have a relatively good prognosis and the disease is not very serious. In addition, Wegener’s granulomatosis, nodular disease, pulmonary vasculitis, silicosis, etc. can also form pulmonary nodules, which are also relatively serious and require active treatment to avoid further aggravation of their conditions.