Group of 12 male and 12 female rabbits was given daily intravenous injections of different dosage of Ginkgo biloba extract(EGb 761), 7.5 mg/kg/day (low dosage group), 15 mg/kg/day (middle dosage group), or 30 mg/kg/day (high dosage group)for 3 month by ear vein according to Established Regulation of Korean National Institute of Safety Research (1994. 4. 14). Appearance, behavior, mortality, and food consumption of rabbits of treated groups were not affected during the experimental periods. No significant Ginkgo biloba extract(EGb 761)-related changes were found in urinalysis, hematology, serum chemistry, and organ weight. No histopathological lesions were seen in both control and treatment groups. Our results strongly suggest that no toxic changes should be found in rabbit treated intravenously with Ginkgo biloba extract(EGb 761)for 3 month.