To explore the combined effect of 1, 25-dihydroxyvitamin D,3,(1,25(OH),2,D,3,) with ,60,Co γ-rays irradiation on the growth of ovarian cancer cell line SKOV-3, SKOV-3 cells were divided into 4 groups: 1, 25(OH),2,D,3, treatment group, irradiation group, combined treatment group and control group. Cell proliferation was determined by MTT. Distributions of cell cycle, ROS and [Ca,2+,]i were analyzed by flow cytometry. The results showed that although each of two treatments alone displayed antiproliferative activity, the growth inhibition of SKOV-3 cells was further enhanced by the combination of 1, 25(OH),2,D,3, with irradiation. Cell cycle analysis indicated that the distribution of SKOV-3 cells in G,0,/G,1, phase was significantly increased by 1, 25(OH),2,D,3, whereas, G,2,/M phase was further increased with its combination with irradiation. The results showed that the contents of ROS and [Ca,2+,]i in the combined group cells were all significantly higher than that of the single treatment group (,P,<,0.05). 1,25(OH),2,D,3, can enhance inhibition of ovarian cancer cells to γ-rays irradiation.