Solitary pulmonary nodule（SPN） is a nearly circular lesion with a diameter of ≤3 cm in the lung

which is mainly surrounded by the lung parenchyma

and the patients do not present with atelectasis

hilar enlargement or pleural effusion.Imaging is the main tool to detect benign and malignant SPN

and the diagnosis of this disease has evolved from pure morphological examination to functional and molecular examination.Benign nodules are usually formed in the early stage of the disease

and if detected in time

they can not only improve the clinical treatment effect

but also have important significance for the quality of life and survival time of patients.In this paper

we review the study on the differentiation of benign and malignant SPN by imaging examination

with the aim of providing a reference for the diagnosis of this disease.