Abstract: A review of earth dams performance during earthguake shows that the damage of dams has Predominately been occurred in the form of vertical cracks parallel to the dam axis. A series of model tests have been carried out for studying the conditions favouring the development of such cracks. Then, based on Miner's cumulative damage theory and random vibration theory a method is presented for the Prediction of cracking resistant behavior of earth dams subjected to earthquake, Finally, the cracking potential of an actual dam has been examined.