The invention relates to an auxiliary supporting device for a pole overhead ground wire and an OPGW optical cable, and the device comprises a supporting rod. The lower half part of the supporting rod is provided with an installation cap which is used for sleeving the top of an electric pole. A left-right symmetric supporting arm is hinged above the installation cap, and a lifting mechanism for enabling the supporting arm to move is disposed between an extending end of the supporting arm and the top of the supporting rod. The extending end of the supporting arm is provided with a lifting hook. The device supports the overhead ground wire for providing a larger operation space for the installation of the overhead ground wire, is simple in structure, is convenient in operation, reduces the number of workers, eliminates the potential safety hazards in an operation process, and improves the work efficiency.