Abstract: In order to study the influence of circular hole obstacles on pressure overlap, different circular hole obstacles were tested to obtain different methane air explosion propagation process by explosion test system. The analysis of the explosion process shows that the size of the round plate has an exponential relationship with the rate of pressure rise; when the size of the round hole is 16 mm, the maximum explosion pressure is 1.129 MPa; when the size of the round plate is 160 mm, the minimum explosion pressure is 0.290 MPa; when the size of the round hole is less than 70% of the inner diameter of the pipe, the pressure overlap will occur.