In the mobile communications of the fifth generation or the like, a radio relay apparatus capable of stably over a wide area realize a three-dimensional network, in which a propagation delay is low, a simultaneous connection with a large number of terminal apparatuses in a wide-range and high-speed communication can be performed, and a system capacity per unit area is large, in radio communications with terminal apparatuses including devices for the IoT, and there is no influence on radio wave frequency resources, is provided. The radio relay apparatus comprises a floating object provided with a radio relay station and controlled to be located in a floating airspace with an altitude less than or equal to 100 [km] by an autonomous control or an external control, an optical communication section for performing optical communication with an optical communication destination via an optical antenna apparatus controllable to change outgoing directional beam, an information acquisition section for acquiring at least one of optical-beam control information provided with a radio relay station and a reception sensitivity of the optical communication section, and a beam control section for controlling a directional beam of the optical antenna apparatus based on information acquired by the information acquisition section.