Exploration and development of new therapeutic radioprotectors is of great concern for both public health and academic research. Combined application of radioprotectors is as a strategy aiming at reduction of toxicity and increase of radioprotective efficacy. We reported previously that Na₃VO₄(VD) had potential biofunctions including suppression of radiation-induced apoptosis and reduction of radiation-induced detrimental effects on fetal mice from a moderate to a high dose(1 ~ 3.5 Gy). These results suggested an abundance of pharmaceutical candidates for possible radioprotectors from inorganic chemicals and pointed to the further investigation on the radioprotective effect by combination of several anti-apoptosis agents against a relatively low dose(0.5 Gy). In the present study, pregnant ICR mice were irradiated with X-rays on E12. Either VD or its combination with a p53 inhibitor(pifithrin) and a pan-caspase inhibitor(Z-VAD) was intraperitoneally administrated at 30 minutes after irradiation. The dams were left for delivery and the neonates were monitored for postnatal development. Administration of VD alone significantly reduced the inhibitory effect on postnatal development, and combined application showed a more statistically remarkable efficacy. These findings indicate that VD could reduce the detrimental effect of prenatal irradiation on postnatal development in mice. Administration of combined anti-apoptosis agents would have a great possibility for clinical application in the future as a therapeutic treatment for low dose radiation exposure.