To provide a radio wave propagation space, e.g. a microwave darkroom, having an inexpensive and simple structure as compared with prior art, and to provide a stable radio communication environment capable of preventing multiplex reflection.

A radio wave propagation room is a space closed by a wall part 11 having a parabolic cross-section, a wall part 12 having a parabolic cross-section and facing the wall part 11, a planar ceiling part 13, a planar floor part 14 facing the ceiling part 13, a planar wall part 15, and a planar wall part 16 facing the wall part 15. When a radio wave is transmitted from a transmitting point T at the focus on the parabolic plane of the wall part 11, it is reflected on the wall part 11 and propagates in parallel with the ceiling part 13 and the floor part 14 to reach the wall part 12 where it is reflected. Furthermore, all transmitted radio waves can be received and absorbed at a receiving/absorbing point R located at the focus on the parabolic plane of the wall part 12.