A battery information acquiring apparatus includes a voltage acquiring unit which acquires an inter-terminal voltage of the battery cell; a battery information acquiring circuit which acquires battery information of the battery cell with the acquired voltage being supplied as a first power supply voltage and; a radio circuit which transmits a signal of the battery information to the management unit via the antenna with the acquired voltage being supplied as a second power supply voltage and; a rectification circuit which receives a radio signal from the management unit via the antenna, rectify the received radio signal and generate a DC voltage; and a control circuit which controls supply of the first and second power supply voltages to the battery information acquiring circuit and the radio circuit wherein the control circuit operates with the generated DC voltage being supplied as a third power supply voltage.