Objective:To evaluate the effect of preoperative transcatheter arterial chemoembolization (TACE) on liver function and survival of patients after resection of large hepatocellular carcinoma (HCC) by a randomized controlled approach.Methods: From July 2001 to December 2003, a total of 108 patients with resectable large HCC（≥ 5 cm）,who met the inclusion criteria,were prospectively randomized into surgical resection group (OP group,n=56) or preoperative TACE group (TACE+OP group,n=52).Operative outcomes,resection rate,1-,3-,and 5-year tumor-free survival rates and overall survival rate were compared between the two groups.Results: The preoperative baseline conditions were equivalent between the two groups.The γ-globulin level in TACE+OP group was significantly higher than that in the OP group（P=0.046）after chemoembolization.The prealbumin level was significantly lower than that of the OP group seven days after operation（P=0.031）.Compared with TACE+OP group,OP group had a significantly higher resection rate (100% vs 89.4%,P=0.017),a less average operative time (P=0.042),and less metastases (2 vs 9,P=0.018).There were no significant differences between the two groups in intraoperative blood loss,warm ischemic time,1-,3-,and 5-year tumor-free survival rates,or overall survival rate.Conclusion: The preoperative TACE can not improve post-operative tumor-free and overall survival rates, and it may result in tumor metastasis or hepatic function damages.