Aim of the work: the purpose of this study was to detect effect of buspirone hydrochloride (Buspar) on the structure of cerebellum cortex of the fetuses of the pregnant rats. Material and methods: buspirone hydrochloride tablets are an antianxiety. Buspirone hydrochloride (buspar) tablets were obtained from SmithKline Beecham-Haram-Giza- Egypt. Thirty pregnant female rats were randomly categorized into three groups (Ten pregnant female rats in each group). Group I (control group) pregnant rats were administered oral doses of distilled water, group II: in this group pregnant rats were treated with buspirone hydrochloride, they were administered oral doses of drug in the distilled water equivalent to 0.27 mg/100g. body weight/day respectively for 15 days from the 6th day to the 20th day of gestation. , group III: pregnant rats were treated with to oral doses of buspirone hydrochloride in the distilled water equivalent to 0.41 mg/100g. body weight/day respectively for 15 days from the 6th day to the 20th day of gestation. Pregnat rats of all groups were sacrificed on the 20th day of gestation and their fetuses were obtained for the histopathological and histochemical studies. Results: treatment of pregnant rats with buspirone hydrochloride (buspar) showed many dystrophic changes in brain of their fetuses; these changes were more obvious in case of the toxic dose of buspirone which resulted in some sorts of neurotoxic structural changes in the cerebellum of fetuses of pregnant rats as evident by deformity in the cerebellar layers and degeneration of Purkinje cells. Conclusions: buspirone hydrochloride (buspar) has many adverse effects on the fetal cerebellum tissue.