Abstract: Objective To assess the clinical value of fluorine-18-2-fluoro-2-deoxy-D-glucose (18F-FDG) positron-emission tomography/computed tomography (PET/CT) in preoperative evaluation of hepatocellar carcinoma (HCC) patients for liver transplantation and in early detection of recurrent foci after the operation. Methods A retrospective study was conducted involving 19 HCC patients undergoing 18F-FDG PET/CT before and after liver transplantation. The pre- and postoperative clinical data and 18F-FDG PET/CT images of these patients were analyzed. Totally 10 18F-FDG PET/CT examinations (in 8 patients) were performed for purpose of preoperative evaluation of the transplantation and assessment of the tumor elimination and general metastasis following the adjuvant therapy, and 22 examinations (in 11patients) performed postoperatively to identify recurrent foci and metastasis. The average time span between 18F-FDG PET/CT examination and the operations was 8.68 months. Results PET examinations in 2 patients for preoperative evaluations showed no evidence of tumor recurrence or metastasis, so they underwent liver transplantation as scheduled. 18F-FDG PET/CT found distinct metastasis in the target operation area in another 2 patients, and liver transplantation was performed with proper management of the metastatic foci. The other 4 patients were found to have distal metastasis, so that operations were cancelled and the patients received interventional therapy and other treatments instead. Postoperative 18F-FDG PET/CT examination discovered no metastatic foci in 2 patients, but detected mycotic brain abscess in 1 patient. Another 19 postoperative 18F-FDG PET/CT examinations (in 8 patients) showed recurrence in the grafted liver (in 4 patients), tumor embolism in the left and right hepatic veins and in the inferior vena cava, in addition to metastasis to the lungs, lymph nodes, bone, spleen, parietal pleura, intervertebral foramen of the thoracic vertebra etc. Conclusion 18F-FDG PET/CT scanning shows superior accuracy in identification of lymph node tumor metastasis. With the advantages of whole-body scanning and high sensitivity of tumor detection, 18F-FDG PET/CT can be instrumental in preoperative evaluation of liver transplantation for HCC (such as modification of the clinical staging) and postoperative early detection of recurrent tumors.