Abstract: For uncertainty and complexity of earth-rock dam aging damage process, AHP-cloud model was applied to finish ageing-injuring risk evaluation of earth-rock dam. First, AHP was used to construct the index system with multiple levels of ageing-injuring risk evaluation about earth-rock dam considering dam-break loss. The cloud model characteristic parameters of index layer and factor layer and comment set were processed quantitatively through established judgment matrix based on contrast scale of cloud model, to identify aging risk degree of earth-rock dam. Finally, every status factor of Shaheji reservoir dam before and after reinforcement was graded respectively and the characteristic parameters of general comment cloud model were calculated, then finished quantitatively the aging risk degree evaluation of earth-rock dam. The results show that this method of aging-injuring risk analysis is feasible and can be used in engineering.