The objective of our study was to determine the effect of an electric field (EF) on the life-span of mice. Male and female mice were paired and separated into two experimental groups: EF exposed and controls. The exposed mice were subjected to a 50 Hz, 10 kV/m electric field for 20 h/day. Offspring from both groups were identified as generation one and allowed to live for 18 months. Offspring from generation one were identified as generation two and allowed to die naturally. The age at which death occurred in both groups was recorded and post mortem examinations were performed. The obtained results were statistically analyzed by means of the chi-squared test. A statistically significant higher incidence of deaths before 18 months occurred in the first generation of the exposed group. The second generation of the exposed group showed a higher incidence of death at an earlier age. No increased incidence of malignant tumors nor any single specific cause of death was disclosed in the exposed animals. The results of this study indicate that continuous long-term exposure to a 10 kV/m electric field may shorten life-expectancy.