The invention discloses an automatic sealing wire port of a power meter box. A wire inlet is connected with a sealing plate, and the sealing plate comprises at least one row of sealing wire ports which are correspondingly communicated with the inner cavity of the box body. The interior of each sealing wire port comprises two sliding grooves which are disposed on the sealing plate and are concave. The sliding grooves are correspondingly communicated with the sealing wire ports. The interior of each sliding groove is provided with a sliding disc which rotates in the sliding groove. Each sliding disc is cylindrical, and is corresponding to one sealing wire port. Two sealing cavities on the sealing plate are disposed between the sliding grooves at two sides. The interior of each sealing cavity is provided with a sealing ring corresponding to one sealing wire port, and can enable a wire to rotate on the rotating disc, thereby further preventing the wire ports on a conventional electric meter box from damaging the wires, further avoiding electric leakage caused by the damages of the wires, and further preventing rainwater from entering into the cavity of the box from the wires.