A radio wave imaging method is proposed, where the radio wave fields are mapped by scanning a small shielding plate in the fields. Since the electric power from the receiver decreases as the shielding plate sweeps across a radio wave field of a stronger intensity, the field pattern can be recorded by displaying the signals received by a fixed receiver. An experiment is conducted with a 10 GHz microwave, where images of planar objects are recor-ded by scanning a small aluminum plate near the objects and displaying the signals from a receiving electromagnetic horn by a CRT. Based on experimental results, applications of this imaging method to the detection of metallic objects in optically opaque dielectric materials and to the visualization of radiation fields from the microwave apparatus are discussed. Fur-ther, this imaging method is discussed from the point of view of radio wave shadowgraphy and holography also with experimental results.