The invention belongs to the technical field of power supply, and provides a multifunctional portable electronic place card and a power supply and information transmission method thereof. The multifunctional portable electronic place card comprises a main circuit board, a lithium battery, a charge and discharge boost protection integrated plate, a communication module, a USB (Universal Serial Bus) data transmission line, a USB connector, a USB female base and a power adapter, wherein the USB female base and the USB connector are both arranged on the main circuit board; one end of the USB data transmission line is connected with the power adapter, and the other end of the USB data transmission line is connected with the USB connector; the charge and discharge boost protection integrated plate is respectively connected with the anode and the cathode of the lithium battery and the USB connector; the lithium battery is connected with the main circuit board and the USB female base; and the main circuit board is provided with a switch, which is used for controlling the on/off of the lithium battery. The multifunctional portable electronic place card provided by the invention can realize the charging and communication functions of the electronic place card simultaneously, and is easy to carry, convenient to use, fast in charging and can prolong the service life.