By using the specially designed experimental device for anchor rope impact tensile, a series of experiments on the possibility of gas explosion detonated by the pull out (broken) sparks of 15.24 mm, 17.8 mm and 21.6 mm anchor rope have been performed on the condition that the gas concentration and oxygen concentration are within the range of explosion limit. The results show that there are 3 failure forms of anchor rope when it is under the action of dynamic load, i.e. tensile failure, pull out and pull failure, and the breakages all occur in the fixed-anchorage. Using infrared thermal imaging apparatus to measure the temperature of the broken sparks of anchor rope, the result shows that the maximal temperature of the pull out (broken) sparks of anchor rope is far less than the minimum temperature of gas explosion (650~750 ℃) and the existence time of sparks is far shorter than the sensitive period of gas explosion. The sparks induced by any failure forms of 15.24 mm,17.8 mm and 21.6 mm anchor rope can’t detonate the gas.