The antitumor effect of 17a-D-homo ethynyclestradiol-3-accetate (DHEA) combined with γ-rays and protective effect of DHEA on hematopoietic function in tumor-bearing mice was studied in this paper. The EC109-inoculated nude mice were divided into four treatment groups as DHEA, DHEA combined with γ-rays, γ-rays only, and control group. The groups with DHEA were continuously delivered drugs for 9 days, and the inhibition rate of tumor, blood count, and nucleated cell in bone marrow were examined 12 days later. The results showed that inhibition rate of tumor in DHEA group increased compared with that of control group; the tumor weight of the irradiated group was lighter than that of DHEA combined with γ-rays group (p<0.01). In DHEA combined with γ-rays group, RBC and Hb were significantly increased compared with that in radiation group. DHEA and γ-rays have synergic effect in inhibiting esophageal cancer growth and DHEA can protect hematopoietic function in radiation-injured mice.Cited