Abstract: In order to study the influences of stereo obstacles on methane explosion characteristics,some stereo obstacles with different shapes were installed in horizontal pipe,and the changes of flame propagation speed,maximum explosion pressure and the rising rate of maximum explosion pressure were measured and analyzed.The results showed that all of the flame propagation speed,maximum explosion pressure and the rising rate of maximum explosion pressure were rised in a remarkable level under the existence of stereo obstacles,especially the flame propagation speed.Methane explosion characteristics were enhanced with the increase of the obstacle rate.On the same level of blockage ratio,the influences of triple prism with right angles were the most significant,and the oblique three prism second.The effects of cuboid were stronger than the cylinder,the influence laws of spiral obstacle were not stable.