An air purifier capable of maximizing air purification capacity thereof while having a minimum installation area. The air purifier including a body, a suction unit arranged at a lower portion of the body, having a suction port to intake air, a discharge unit arranged at an upper portion of the body, having a discharge port to output the intake air, a blowing unit arranged within the body, to blow air from the suction unit to the discharge unit, and a filter unit arranged within the body, to purify the blown air, wherein at least one of the suction port and the discharge port has a surface that is inclined from a central axis of the body, wherein the filter unit has a filter surface, through which air passes, the filter surface being inclined from the central axis.