Abstract: Objective To investigate the diagnostic value of xSPECT/CT-based tomographic fusion imaging in children with bone metastases. Methods Clinical and imaging data of 152 children with suspected bone metastases examined in our department were collected. All children underwent whole-body bone imaging, xSPECT/CT, and SPECT/CT tomographic fusion imaging. xSPECT/CT and SPECT/CT tomographic fusion images were compared and analyzed to evaluate the diagnostic value of xSPECT/CT tomographic fusion imaging in children with bone metastases. The diagnostic confidence of nuclear medicine physicians of two methods was also compared. Results The sensitivity, specificity, and accuracy of xSPECT/CT tomographic fusion imaging in the diagnosis of bone metastases in children were 93.3%, 91.5%, and 92.8%, respectively; the sensitivity, specificity, and accuracy of SPECT/CT tomographic fusion imaging in the diagnosis of bone metastases in children were 85.7%, 85.1%, and 85.5%, respectively. xSPECT/CT tomographic fusion imaging could improve the diagnostic confidence of nuclear medicine physicians and the difference was statistically significant 5 （2-5） vs. 3 （2-4）, P < 0.05. Conclusion xSPECT/CT tomographic fusion imaging can effectively enhance the diagnostic confidence and diagnostic efficacy of nuclear medicine physicians in the diagnosis of bone metastases in children, which can help to diagnose bone metastases in children at an early stage, and further improve their clinical prognosis.