A navigation satellite system reception apparatus including a satellite orbit information acquisition unit that acquires orbit information of a navigation satellite, an installation position information acquisition unit that acquires position information of an installation position, an azimuth meter that acquires azimuth information of an azimuth in which a wall surface of a nearby obstruction extends, and an azimuth mask generation unit that calculates a mask region for selecting a navigation satellite to be a target of processing based on the azimuth information. A positioning and time synchronization processing unit calculates an azimuth and an angle of elevation of each navigation satellite based on the orbit information and the position information, selects a navigation satellite to be a target of processing, and performs at least one of the positioning processing or the time synchronization processing based on a received navigation satellite signal.