The invention discloses a gas discharge tube tripping device and a signal lightning protection system. The gas discharge tube tripping device is composed of a base, a three-electrode gas discharge tube, a first insertion piece, a second insertion piece and a third insertion piece. The three-electrode gas discharge tube is embedded in the middle of the base. The direction of a pin in the middle of the three-electrode gas discharge tube is opposite to the direction of the other two pins. The relative positions of the first insertion piece, the second insertion piece and the third insertion piece can be changed according to the magnitude of the lightning current, and therefore a failure warning signal is generated when the lightning current is excessively large and the second insertion piece and the third insertion piece are closed, and is sent to a warning signal processing circuit or a remote monitoring circuit, and the problem of failure warning and remote monitoring of a signal lightning protection circuit in the prior art is effectively solved.