An air purifier including a body including a suction port and a discharge port disposed on opposing surfaces thereof, and having an inner space through which air flows from the suction port to the discharge port, a fan disposed in the inner space and having a side surface separated from an inner wall of the body, at least one light source module disposed in the inner space to emit UV light, a power controller mounted on the inner wall and connected to a power source to supply electric power to the light source module, a cover mounted on the inner wall to cover the power controller, and at least one filter disposed in the inner space of the body, in which the cover includes a tilted air flow guide facet to guide tilted to allow air suctioned through the suction port toward the filter.