An air purifier includes a case that includes an air inlet and an air outlet, a tank that is arranged in the case and stores liquid, a fan that causes an air flow from the air inlet to the air outlet to be produced, a partition that is arranged in the case and includes a filter that causes the air flow and the liquid to come into contact with each other while allowing the air flow to pass through the filter, and a plasma generator that includes a pair of electrodes arranged in a first space between the air inlet and the partition and a power supply and generates plasma so that the plasma comes into contact with the liquid.