According to one embodiment, an RFID tag position detection apparatus includes a transmission antenna, at least four reception antennas, and a measurement unit. The transmission antenna transmits a command to an RFID tag. At least four reception antennas receive a response from the RFID tag and output a reception signal. The measurement unit measures time differences between timings at which the reception signals are output from the respective reception antennas and calculates relative coordinates of the RFID tag with respect to a position of the RFID tag position detection apparatus based on the respective measured time differences.