Metavanadate was evaluated for developmental toxicity in pregnant Swiss mice. Sodium metavanadate (NaVO3) was administered intraperitoneally on d 6–15 of gestation at doses of 0, 2, 4, or 8 mg/kg/d. On gestation d 18, all live fetuses were examined for external, visceral, and skeletal malformations and variations. Maternal toxicity was observed at 2, 4, and 8 mg/kg/d as evidenced by decreased weight gain during treatment. Increased resorptions and dead fetuses, increased percentage postimplantation loss, and reduced fetal body weight per litter were observed at 4 and 8 mg/kg/d. There were no significant increases in the type or incidence of external and skeletal anomalies, but a significant increase in the incidence of cleft palate was detected at 8 mg/kg/d. The lowest‐observed‐adverse‐effect level (LOAEL) for maternal toxicity was 2 mg NaVO3/kg/d, while 2 mg/kg/d was also the no‐observed‐adverse‐effect level (NOAEL) for significant developmental toxicity.