The differential diagnosis of benign and malignant solid nodules in the lungs is mainly made through the following aspects, namely, imaging examination, blood test and pathological biopsy. 1. Imaging examination: benign nodules generally have smooth edges and uniform density, and have little effect on the surrounding tissues; malignant nodules generally have uneven edges, visible burrs and lobes, uneven density, and partially visible pleural pulling. 2. Blood test: benign nodules in the lungs usually do not show obvious abnormality in blood test indicators; malignant nodules will be accompanied by the rise of tumor markers. 3. Pathological biopsy: through pathological puncture of benign nodules, the cells are normal differentiated cells; malignant nodules can generally find differentiated cells, the lower the degree of cell differentiation, the higher the degree of malignancy. Considering malignancy through the examination of nodules in the lungs, it is necessary to consult a doctor in time for observation, and after confirming the diagnosis of the disease, carry out standardized treatment under the guidance of clinicians to avoid delaying the disease.