Disclosed herein a pharmaceutical composition, comprising obovatol as an active ingredient, for the prevention and treatment of neurodegenerative diseases. Having superior inhibitory activity against the production of neurotoxic nitric oxides, the obovatol isolated and purified from Magnoliaceae can be used as active ingredient for a pharmaceutical composition or a neuroprotective agent for the prevention and treatment of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis.