A compressive fatigue testing method of polymer bonded explosive (PBX) was introduced and experimental studied with JB-9014. The frequency of fatigue loading sine was fixed at 2 Hz and the maxium compressive stress was 20.98,22.3,23.6,25.5,26.5 MPa . The S-N curve which is fitted well with exponential law has been obtained. Based on S-N curve, compressive fatigue limit at 20.98 MPa (70% of the comparative strength limit of the PBX) is computed out,Viz.10⁶cycles. It indicates that JB-9014 has nice assist-fatigue charactaristic.