A contact-free data communication system includes a data communications device located in a predetermined place and a contact-free identification tag. The data communications device includes a first data controller and a data global positioning system that acquires positional information of the data communications device and a transmitter that transmits an electromagnetic wave for providing power and transmits the positional information of the data communications device to the contact-free identification tag in a surrounding area of the data communications device. The contact-free identification tag includes a receiver that receives positional information transmitted by the data communications device, a power generator that generates driving power out of the electromagnetic wave for providing power that is transmitted by the data communications device, a generator that generates positional relationship information based on the positional information that is received by the receiver, a display that displays positional relationship information that is generated by the generator, a data storage medium that is nonvolatile and a data storage that stores data in the storage medium.