To suppress the generation of unburnt materials such as 'soot' in a combustion device and improve ignitability (startability).

A plug 131 and a wick 130 are disposed in a main combustion tube 122 (main combustion chamber 122a) so as to axially extend along a central axis to an orifice 124a side from a bottom plate part 122c. First air holes 122d are provided in the tube 122b of the main combustion tube 122. Thus, an air-fuel ratio can be made substantially the same in any part in the axial direction. Accordingly, since the air-fuel ratio of all the main combustion tube 122 can be set to a desired state (ideal air-fuel ratio), the unburnt materials such as 'soot' are hardly produced even when a combustion is carried out for a long time. Since the wick 130 is disposed in the center of the main combustion tube 122, the volume of the wick 130 can be made smaller than that of a cylindrical wick system. Thus, the ignitability (startability) of the combustion device 100 can be improved.