To provide a method and a device for correcting a radio wave absorbing body with which the radio wave absorbing performance in matching with a design frequency can be set with high accuracy.

A radio wave, swept from a signal generator 2 within a prescribed frequency range, is emitted to an optional part of a radio wave absorbing body A, a reception processor 3 detects a frequency, at which the absorption indicates a highest peak from data of a reflected wave, a measurement processing section 6 stores the frequency providing the highest peak of absorption together with position information and a drive control section 8 controls a turntable 1, so that the reception processor 3 detects the frequency, while scanning the entire face of the radio wave absorbing body A. A correction amount control section 7 calculates the correction amount required for an absorbing layer from the difference between a frequency providing the maximum peak frequency of the absorption at each position and the design frequency and an ink coater 4 coats conductive ink to the absorption layer, in response to the correction amount at each position so as to adjust the thickness of the absorption layer.