Objective To analyze the imaging features and clinical significance of solitary costal hot spots in patient with lung cancer on SPECT/CT fusion imaging and the value of low-dose CT for diagnosis.Methods SPECT/CT scan was performed on 68 patients with lung cancer and costal single hot spots using whole body bone imaging.The sites of lesions were classified into four types:junction between costal cartilage and rib,frontal rib,lateral rib,posterior rib.The shapes of lesions were classified into two forms:punctiform and strip shapes,and were analyzed and classified.The differences of the diagnosis of whole body bone imaging and SPECT/CT scan were analyzed.Results Punctiform spots were mainly due to costal fractures(36/68,52.94％).The majority of spots in strip shape were costal metastases (21/23,91.30％).The lesions of junction between costal cartilage and rib were punctiform shape and benign.Hot spots in posterior ribs were mainly costal metastases (18/22,81.82％).Sensitivity of diagnosis of the metastatic bone tumor with whole body bone imaging and SPECT/CT in single hot spot of spine and rib was 69.23％ (18/26) and 92.31％(24/26),specificity 59.52％(25/42) and 85.71％(36/42),accuracy 63.24％(43/68) and 88.24％ (60/68),positive predictive value 51.43％ (18/35) and 80.00％ (24/30),negative predictive value 75.76％ (25/33) and 94.74％ (36/38).SPECT/CT scan had differences with whole body bone imaging in sensitivity (P ＜ 0.05),SPECT/CT scan had significant differences with whole body bone imaging in coincidence and specificity (P ＜ 0.01).Conclusions Useful imaging features can be obtained from SPECT/CT fusion imaging with single costal hot spots,being helpful to differential diagnosis of benign and malignant lesions.SPECT/CT fusion imaging may improve the accuracy to diagnose the rib disease.