Abstract: Objective: To investigate the effects of 3-dimentional conformal radiotherapy (3DCRT) combined with TACE on primary heptic carcinoma (PHC) and its fractionated dose and total dose. Methods: A total of 60 patients with PHC were randomly divided into two groups: the 3DCRT plus TACE group(n=30) and the TACE group (n=30). Such treatment was performed twice in the TACE group and the interval was 4 weeks. In the 3DCRT plus TACE group, the above treatment was performed once, and 3DCRT was started at 1-3 weeks after TACE treatment. 3DCRT was given by 6MV Xray, with a planned target volume(PTV) of 55Gy in total dose, 5Gy per session, 5 times every week. Results: The response rates (CR+PR) of the 3DCRT plus TACE group and the TACE group were 90% and 63.3%, respectively, with a statistical significance (χ²=5.963,P=0.015). The 1-, 2-, and 3-year survival rates of 3DCRT plus TACE group and the TACE group were 86.7%, 53.3%, and 33.3%, and 53.3%, 36.7%, and 16.7%, respectively. The median survival was 26.5 months(5.4 to 59.3 months) in the 3DCRT plus TACE group and 15.8 months (6.3 to 40.7 months) in the TACE group (χ²=7.68,P<0.01). In the patients with portal vein tumor thrombus, the 1-, and 2-year survival rates were 69% and 7.7% in the 3DCRT plus TACE group and were 12.5% and 0% in the TACE group. Their median survival was 13 months(5.4 to 25.5 months) in the 3DCRT plus TACE group and 8 months (6.3 to 12.6 months) in the TACE group, respectively (P=0.0237). Conclusion: 3DCRT combined with TACE is more effective than TACE. 3DCRT started at 1-3 weeks after TACE treatment with a total dose of 55Gy, 5Gy per session, 5 times every week is feasible. When PTV is more than 1000cm3 and liver function is Child B, a total dose of 50Gy will be safer.