Objective To investigate the relationship among 18 F-fluorodexyglucose (FDG) PET, pattern of lipiodol retention CT and serum ?-fetoprotein(AFP) in evaluating the effect of transcatheter arterial chemoembolization(TACE) for hepatocellular carcinoma (HCC). Methods TACE was performed in thirty-five patients with HCC. 18 F-FDG PET and lipiodol-CT examination were performed after TACE, and thus the patterns of lipiodol retention, and the tumor necrosis rates semi-quantitatively by 18 F-FDG PET were obtained with simultaneous calculation of the decrease percentage of serum AFP before and after TACE. Results The patterns of lipiodol retention were divided into four types; A. dense type (n=12), B. rarity type (n=13), C. scattering type (n=7) and D. empty type (n=3). The positive correlation between the tumor necrosis rate (7%～95%) and the decrease percentage of AFP(0～100%) were found (r=0.761 P