The invention relates to flavanone derivatives, and preparation method and use thereof, particularly relates to a compound of Formula I or a pharmaceutically acceptable salt thereof, a pharmaceutical composition comprising the same, a preparation method thereof, and use thereof for preventing or treating a mental disorder or a nervous system disease. The compound of the invention exerts significant activity of inhibiting microglial activation and neuroinflammation, can antagonize dopamine D2 receptor, improve the ethological change in multiple animal models for mental disorders, effectively inhibit neuroinflammation and demyelination, and can be used to prevent or treat a mental disorder and a nervous system disease.