Potato glycoalkaloids were extracted from potato sprout and then analyzed to determine their purity by using TLC and HPLC methods and compare with pure alpha-Solanine and alpha-Chaconine of Sigma. The result indicated that the purity of potato glycoalkaloids is 78. 31%, which contains 73.64% alpha-Solanine and 4.67% alpha-Chaconine. The LD50 of mice was 44.721 +/- 5.860 4 mg/kg. In order to determine the toxicity and teratogenicity of potato glycoalkaloids, the effect of potato glycoalkaloids on Kunming pregnant mice were studied. The results showed that: (1) potato glycoalkaloids have teratogenic effects on embryos of mice. It could induce neural tube defects (NTDs), and may be an important teratogen of NTDs. (2) potato glycoalkaloids have embryo toxicity. It could cause the death of embryos and result in absorbed and dead fetuses. (3) potato glycoalkaloids could evidently affect the development of embryos and lead to intrauterine growth retardation (IUGR). An interesting phenomena which just like the clinical manifestation of miscarriage in human being was noticed. If potato glycoalkaloids were given to the pregnant mice on the 5th or 6th day of gestation intraabdominally, vaginal bleeding and abortion would occur, and this has not been reported yet. The animal model of NTDs in this experiments supported our hypothesis that sprouted potato could be a teratogen of NTDs.