To investigate the impact on survival of HIF 1-alpha expression on primary advanced epithelial ovarian cancer (EOC), we examined the correlations between prognosis and HIF 1-alpha expression by Western blot analysis in 52 cases of stage III/IV EOC. HIF 1-alpha expression was confirmed in 36 cases (69.2%) of EOC, and HIF 1-alpha-expressing tumors had a significantly higher rate of response (p<0.01) to postoperative paclitaxel/carboplatin combination chemotherapy (TC) than tumors without HIF1-alpha expression. Moreover, patients with HIF 1-alpha-expressing tumors with suboptimal resection of stage III/IV tumors indicated for postoperative TC exhibited significantly better survival (p<0.01).