Abstract: Objective To evaluate the clinical value of ¹⁸F-fluorodeoxyglucose(¹⁸F-FDG) PET-CT imaging in detecting breast cancer.Methods 60 patients with suspicious masses underwent ¹⁸F-FDG PET-CT imaging, mammography and ultrasonography respectively. The results of the histopathology after surgery were used as diagnostic golden standard. The uptaking of ¹⁸F-FDG in the breast masses was analyzed using semiquantitative and qualitative methods. The findings of PET-CT,mammography and ultrasonography in detecting breast cancer were compared.Results 48 malignant and 12 benign breast lesions of the 60 patients were proven histologically after surgery. The sensitivity, specificity, accuracy and positive predictive value obtained by PET-CT were 93.8%,83.3%,91.7% and 95.7%, respectively, and which were 81.3%,83.3%,81.7%,95.1% and 85.4%,83.3%,85.0%,95.3% with mammography and ultrasonographic. In the diagnostic ability among the three methods there was no significant difference showed(χ²=3.40,P>0.5).Conclusions PET-CT has higher degree of sensitivity, specificily and higher positive predictive value in breast cancer diagnosis and staging comparing to the mammography and ultrasonographic.