To provide an air cleaner which suppresses a reduction in discharge performance and is low cost.

The air cleaner of this invention has a discharge electrode 4 having an electron emitting part, a counter electrode 5 arranged at an interval from the discharge electrode 4, a power source device 6 for applying electric potential for generating the discharge between the discharge electrode 4 and the counter electrode 5, and a ventilation means 2 for flowing the air to be cleaned between the discharge electrode 4 and the counter electrode 5. In the air cleaner in which a component to be cleaned in the air is cleaned by discharging between the discharge electrode 4 and the counter electrode 5, the electron emitting part is a carbon nano-tube protruding in the counter electrode 5 direction. The air cleaner of this invention is the air cleaner which suppresses the reduction in the discharge performance and is low-cost.