PURPOSE: To improve resolution by comparing tomographic information, obtained by transmitting a wave having a frequency absorbed singularly through each human anatomy, with tomographic information of a wave having a nonsingular frequency.

CONSTITUTION: From an oscillator 1, a microwave having a frequency f1 absorbed by resonance by, for example, a cancerous cell (a), is inputted to a living body A through an antenna 2. Its transmitted wave is received by an antenna 3 and an information group S1 is inputted to a computer system 5 through a detector. Then, the same measurement is performed near the cancerous cell (a) at a frequency f2 at which any human anatomy does not resonate to obtain an information group S2. Those information groups S1 and S2 are used to extract information on the cancerous anatomy by removing the influence of scattering, etc., thereby displaying a cancer image Sg on a picture display device 6. Consequently, the influences of attenuation and scattering are removed to improve the resolution of microwave computer tomography.