Lung nodule 2mm belongs to the lung micro-nodule, most of them are benign, regular follow-up can be, but should also pay attention to distinguish between benign and malignant nodules, should be timely consultation, improve the relevant examination to clarify the cause of the disease. 1. Benign nodules: (1) Inflammatory pseudotumor: it is a non-neoplastic lesion caused by certain non-specific inflammatory proliferation, and pathologically it is a granulomatous structure with multiple cellular components; (2) Benign lung tumors, including: malignant tumors, chondromas, fibromas, smooth muscle tumors, hemangiomas and lipomas, bronchiolar cystadenomas or papillomas. This type of nodule 2mm smaller, not serious, generally asymptomatic, can be followed up and observed. 2. Malignant nodule: such as lung cancer, whether it is serious or not depends on the clinical stage. If there is no lymph node metastasis or distant metastasis, it is considered early stage, and surgical treatment can usually achieve curative effect. If there are lymph node metastasis or distant metastasis, then it is intermediate-late stage, which is more serious, but surgical treatment, chemotherapy, radiotherapy and targeted therapy can be used to prolong the survival period of the patient and alleviate the symptoms. Therefore, when you find lung nodules, you should consult a doctor to clarify the nature of the lung nodules and follow up or treat them according to the doctor’s instructions.