Objective To explore the CT appearances of solitary pulmonary metastases(SPM)in order to improve the level of CT diagnosis of SPM.Methods The CT findings of 21 cases with SPM proved by pathology were analyzed retrospectively . Results 1.The distribution of lesions:in 21 cases with SPM were:10 ( 47.6% ) niduses in left lung , 11 ( 52.4% ) lung in right ;3 (14.3% ) in bilateral superior lobuses ( excluding segmentum lingulare ),5 ( 23.8% ) in lobus medius and segmentum lingulare,13 ( 61.9% ) in inferior lobuses;14(66.7%)in external 1/3 of lung field,5(23.8%)in middle 1/3 and 2(9.5%)in interior1/3; 2.The diameter of lesions were:d3 cm(4,19.0%). 3.The shape and the margin of lesions were:circular or ellipse niduses with smooth surface and clear tumor-lung interface in 15 ( 71.4% ) ,irregular-shaped niduses in 6 ( 28.6% ) , with lobulation sign in 3 , spiculae in 2 , pleural indentation,bronchovascular bundles and halo in 1 respectively ; 4.The density of lesions were:Uniform soft tissular density in 16 cases(76.2%),calcification in 2,cavity in 1 and necrotic area in 2; 5.In all 21 cases,it was not found that SPM invaded bronchi nearby .Conclusion SPM has some certain characterizes on CT,but only by combining CT appearances with clinic and pathology,its correct diagnosis can be done.