In mammal, lots of follicles start simultaneously their growth but only a few oocytes are ovulated in every sexual cycles. Most of matured and grown oocytes are destined to degenerate by atresia. However, the molecular and physiological mechanisms are not elucidated yet. The present study was designed to establish an induction method of follicular atresia with ketamine or pentobarbitone and evaluate the effect of these anesthetics on oocyte maturation and granulosa cell apoptosis of the mouse ovarian follicle. The percentages of degenerated oocyte and apoptotic granulosa cell in ketamine treated groups were significantly higher than that in controls (58.9% vs 33.5%, p<0.01, degeneration; 44.9% vs 26.6%, p<0.01, apotosis). Futhermore, it was revealed that the concentrations of progesterone in both groups were markedly higher than that in control. In conclusion, it is considered that ketamine induce an atresia as pentobarbitone, and may be useful for inducing follicular atresia.