Abstract: To solve the problem that the drainage efficiency decreases due to the system change of underground gas drainage pipe network, a graph theory model was established based on various characteristics of the drainage system. The concentration and mixed traffic flow of gas was assigned as the parameters of node weights. The pipe length and diameter were assigned as the parameters of link weights. The resistance loss of each section of pipe network is obtained by the theories of Origin-Destination calculation of flow concept and pipeline resistance calculation. The location of the optimized pipe segment and the optimal scheme and parameters are determined. After optimizing the extraction area of 8210 in Luling Coal Mine, the resistance loss of the optimized pipe section was reduced by 8 times, and the extraction scalar in the optimized area was increased by more than 1 times.