Abstract: Objective : To investigate the clinical evaluation of ¹⁸F-FDG PET imaging in diagnosis and therapy of nasopharyngeal carcinoma. Methods : 35 patients with nasopharyngeal carcinoma underwent ¹⁸F-FDG PET. The results of PET were evaluated and compared with CT、M R I and ECT. The patients were confirmed by pathology. Results : In 35 cases of nasopharyngeal carcinoma, PET finding were consistent with the CT、 MRI and ECT in 31(88.6%), but not in 4(11.4%). In 1 case with m ultiple bone metastasis, 1 case with recurrent nasopharyngeal carcinoma, 1 case with hepatic metastasis, 1 case with pons cerebelli metastasis, positive sites were not found by PET. 6 (17.1%) cases with remote metastatic lesions were detected by PET. These metastatic lesions were not detected by CT、MRI and ECT. Conclusions :¹⁸F-FDG PET is a valuable method in the diagnosis of nasopharyngeal carcinoma with higher accuracy and specificity. PET is superior to CT and M R I in detection of lymph node and remote metastatic lesions. False negative were found in PET imaging in detection of liver and intracranial metastatic lesions. It s the best way to combine m ultiple imaging analysis of PET and CT or MRI.