In this study, to find out the reason of fatigue fracture of crane runway girder(CRG), theoretical and experimental research on the dynamic behavior of CRG was carried out. The Primary object of research is to find the dynamic behavior and fatigue phemomena of CRG under the crane moving load and lifting load. In dynamic analysis, finite element method is used to solve the equilibrium differential equation governing linear dynamic response of CRG. To predict the fatigue life of CRG, The Palmgren-Miner hypothesis as the linear cumulative fatigue damage theory is used. Linear cumulative fatigue damage D was calculated in accordance with linear damage rules.