PURPOSE: To miniaturize a far-infrared air warmer and improve the efficiency of far-infrared radiation.

CONSTITUTION: An outer side reflective tube 12 surrounding a far-infrared heater 11 is disposed in a tubular housing 10. A plurality of recessed grooves 15 are provided on the surface opposed to the far-infrared heater 11 with first and second inclined surfaces 21, 22 from the intake port 5 side toward the discharge port 6 side. The first inclined surface 21 is inclined at 45° or less angle θ1 toward the intake port 5 side and the second inclined surface 22 at 45° or more angle θ2 toward the discharge 6 side. Most of the far-infrared rays radiated from the far-infrared heater 11 to the outer side reflective tube 12 side are reflected to the disckharge port 6 side by the first inclined surface 21.