The present invention relates to an air purifier, comprising a housing, an air dynamic unit, an ultraviolet light-emitting unit, an evaporation container for accommodating neutralizer, and a catalyst device. The air dynamic unit is disposed at the inlet of the housing. The ultraviolet light-emitting unit and the catalyst device are disposed in the housing. The present invention uses the light-emitting unit and the catalyst device to purify the air and exhaust the purified air via the outlet of the housing.