A positioning server device comprises: an input unit which receives measurement information of radio waves which are transmitted between an access point and a client; a radio wave map administration unit (10) which administers radio wave map data which denotes an estimation of a correspondence relation between the radio wave measurement information and a spatial location; and a positioning unit (13) which positions the location of the client based on the radio wave measurement information and the radio wave map data. The radio wave map administration unit (10) administers first map data which relates to a fixed positioning range where it is possible for a client to be positioned to be present conventionally, and second map data which relates to an extended positioning range wherein a possibility arises that the client to be positioned may be present according to particular conditions, as radio wave map data.