To achieve high-load combustion of a combustion apparatus for a gas clothes dryer by shortening flames and cooling combustion chambers by controlling a feeding position and direction of secondary air.

The combustion device comprises a primary combustion chamber 12 provided with a single opening A 12a on an upper part wherein a burner 11 having a plurality of flame holes is faced inside, a secondary combustion chamber 14 provided with a single opening B 14a on an upper part wherein the primary combustion chamber 12 is faced inside, a main combustion chamber 16 provided with a single opening C 16a on an upper part wherein the secondary combustion chamber 14 is faced inside, and a guide plate 19 disposed in the main combustion chamber. Thereby, shortening of outer flames and cooling of each combustion chamber wall can be achieved.