Objective To investigate the diagnosis and differential diagnosis of pleural solitary lesions (PSL) in patients without history of malignant tumor. Methods Collect information from 89 PSL patients with no history of malignant tumors. Through the analysis of pathological types of malignant tumors and CT imaging features to explore the possibility of qualitative diagnosis of such lesions. Chi-square for statistical analysis. Results There were 10 cases of metastatic lesions group, 13 cases of no-metastatic lesions group, and 66 cases of benign lesions group in 87 cases of PSL. The difference of correlation between PSL of different pathological types and the size of lesions was statistically significant, P<0.05. There was no significant correlation with the other CT imaging feature, P>0.05. There are statistically difference in the relationship between different types of PSL in metastatic lesions group, no-metastatic lesions group, and benign lesions group, the morphological characteristics of the PSL, whether the edges are clear, whether they are accompanied pleural water, freezing, internal necrosis, and size of the lesions, P<0.05. Conclusion The morphological characteristics of the PSL, whether the edges are clear, whether they are accompanied pleural water, freezing, internal necrosis, and size of the lesions can be used as the basis for the identification of the qualitative diagnosis.