A burner structure is provided to independently adjust the amount of air according to air supply systems by separating a secondary air supply system from a cooling air supply system. A burner structure comprises a fuel mixing system, a secondary air system and a cooling air system. The fuel mixing system including a dust coal mixing path(11) is disposed in the center of a burner(10A) to mix fuel with primary air. The secondary air system including a secondary air path(12) is disposed at an outer circumference of the fuel mixing system. The cooling air system including a cooling air path(13) is disposed at an outer circumference or upper/lower sides of the second air system. A nozzle body(17) is installed at a fuel side of the fuel mixing system and the secondary air system. The nozzle body is provided at a front end with a flame holder(16). A cooling air nozzle(18) is installed at a fuel side of the cooling air system.
