Small lymph nodes in the lungs mostly refer to small lymph nodes near the hilum, and there are both normal and abnormal small lymph nodes near the hilum. In normal people, small lymph nodes are present in the lungs themselves, so imaging can indicate small lymph nodal shadow, especially chest enhancement CT can directly indicate small lymph nodes in the hilum. If the small lymph nodes increase in size, especially if they are abnormally large and increase in size, and if there are other infections or even tumor lesions in the lungs, it is important to be alert to the fact that the small lymph node shadow is a metastasis of the mass. Long-term smoking and exposure to dust, especially in the work of masons and coal mines, can early appear small lymph node shadow in the hilum and lung, which is the result of the action of the immune system of the body of the patient after exposure to dust, and this condition is neither infectious nor metastatic, but just a normal reactive hyperplasia, and no special treatment is needed.