AIM:To investigate the efficacy of 99Tcm-octreotide orbital imaging combined with magnetic resonance imaging(MRI)in stage diagnosis of thyroid associated ophthalmopathy(TAO). METHODS: Retrospective analysis of clinical data of 35 surgically treated TAO patients admitted to hospital from June 2017 to June 2018. 99Tcm-octreotide orbital imaging and MRI were performed, and the pathological observation and stages were performed. The result of pathological staging was statistically analyzed. The imaging findings and results of 99Tcm-octreotide orbital imaging combined with MRI were observed. The efficacy of 99Tcm-octreotide orbital imaging, MRI, 99Tcm-octreotide orbital imaging combined with MRI in the stage diagnosis of TAO was analyzed. RESULTS: Totally 58 eyes with TAO in 35 patients with pathological stages were 49 eyes in the active phases and 9 eyes and inactive phases. 99Tcm-octreotide orbital imaging and MRI diagnosis of TAO severity staging have typical imaging findings, and the sensitivity, specificity, accuracy of 99Tcm-octreotide orbital imaging combined with MRI in the diagnosis of active TAO was higher than that of 99Tcm-octreotide orbital imaging and MRI alone. The ROC results showed that the AUC of the active phase of 99Tcm-octreotide orbital imaging combined with MRI diagnosis was 0.893, which was higher than that of 99Tcm-octreotide orbital imaging or MRI alone. CONCLUSION:It is recommended to use 99Tcm-octreotide orbital imaging and MRI imaging in combination with TAO stage diagnosis. The imaging findings are typical, and the combined application has higher diagnostic efficiency.