the purpose of the present invention is to provide a small electromagnetic wave detection apparatus . this electromagnetic wave detection apparatus has : a planar luneburg lens , which is covered with metal plates facing each other , and which changes the output direction of electromagnetic waves corresponding to the input direction of the electromagnetic waves ; and an electric field sensor electrically connected to the metal plates . the electric field sensor detects the electromagnetic waves outputted from the luneburg lens , and outputs a detection signal having an intensity corresponding to the direction in which the electromagnetic waves have traveled thereto , and the level of the energy of the electromagnetic waves thus detected .