Objective To investigate the value of 99Tcm-3PRGD2 SPECT/CT imaging in the diagnosis of benign and malignant lung lesions.Methods A retrospective analysis of 99Tcm-3PRGD2 planar imaging and chest SPECT/CT imaging with lung lesions before treatment was performed.Totally 37 cases including 27 malignant and 10 benign lesions confirmed pathologiclly were enrolled.Compared with hepar in planar imaging,the intake gray scale of 99Tcm-3PRGD2 in lung lesions was divided into low,moderate,and high elevations.The ratio of the highest intake value of the lesion (L) to the contralateral normal lung (N),the hepar (H),the mediastinum (Me) and the contralateral deltoid muscle (Mu) was calculated,and statistical analysis was performed to evaluate the diagnostic efficacy.The expression of immunohistochemistry integrin αvβ3 was performed through selecting 1 case of benign and malignant lung lesions,respectively.Results The intake of 99Tcm-3PRGD2 was higher in 37 patients with lung lesions.High elevation of malignant lesion was 66.67％ (18/27),low and moderate elevation of benign lesion was 90.00％ (9/10).The intake ratio of malignant lung lesions was higher than that of benign lesions (all P＜0.05).When L/N was greater than 5.45 or L/Mu was greater than 4.65,the sensitivity,specificity and accuracy of diagnosis of lung malignant lesions was 77.80％,80.00％ and 78.40％,respectively.Immunohistochemical results showed that malignant lung lesions highly expressed integrin αvβ3,and only a small number of benign lesions expressed it.Conclusion 99 Tcm-3PRGD2 SPECT/CT is valuable in the differential diagnosis of benign and malignant lung lesions.