Abstract: Disclosed is a display terminal device including a display operating unit (12), a first communication unit (22), a reader/writer circuit (24) and a controller (26). The display operating unit is provided on a main body unit (11) to display advertisement data, and the first communication unit communicates with a host device. The reader/writer circuit is provided on the main body unit (11) and communicated with the memory from the display operating unit (12) side to write and/or read out data relevant to the advertisement data. The controller allows advertisement data received by the first communication unit (22) to be displayed on a display operating unit (12). The controller causes data written and/or read out by the reader/writer circuit (24) to be transmitted to or received from a host device or another device via the first communication unit (22).