To solve the problem that it is impossible to efficiently burn wood pellets of all manufacturers through complete burning, due to a burning method in the conventional pellet stove having difficulties of: tendency of production of soot and tar in a pot after fuel burning, updraft peculiar demerit as the main demerit; unevenness of fuel burning on a fire grate; incompleteness in forming a flow of oxygen for promoting secondary or subsequent burning; and a wide range of existing standards of the wood pellets.

By installing a pot shield on a burning pot and making a fire grate in a two-stage structure, the merits of both the updraft and downdraft can be utilized to configure a pellet stove capable of evenly supplying oxygen necessary for burning, converting fuel into heat energy without waste, and ensuring high burning efficiency.