Lung nodules with high density and clear margins are generally not serious if they are benign, while malignant nodules are relatively serious. Nodules occurring in the lungs are divided into two categories: benign and malignant. Lung nodules with high density and clear margins are mostly benign nodules, such as tuberculosis, lung inflammation and other lung diseases, but malignant nodules cannot be ruled out, which need to be diagnosed by perfect pathologic examination. Generally speaking, after effective anti-tuberculosis and anti-inflammatory treatment, most of the lung nodules can disappear or shrink, which has little effect on the quality and duration of life of patients. For malignant nodules should be actively surgical treatment, postoperative regular review, so as not to delay the condition.