Abstract: In the light of the sudden leakage occurred in long-distance gas transmission pipeline, an effective first-aid repair method, a non-shutdown and without pipe replacement method, to deal with it is put forward on the basis of analyzing the all first-aid repair methods for the long-distance gas pipeline. In the article, the operation principle and in-line pipe replacement procedures of this method are introduced, also the shortcomings of the method are given. The advantage of the method is that the accident pipe section can be replaced on the in-line basis way, or the shutdown time can be decreased to a considerable degree, and non-loss or lower-loss and high safety of pipeline can be realized with this method.