Disasters threaten mankind and degrade our survival conditions，and have a serious impact on human society. Several previous disaster spreading models in complex networks are reviewed. Based on the evaluation of their advantages and disadvantages，a more realistic model in the networks with redundant systems is proposed. For different models in different network structures，the differences of spreading processes and the effects of some important parameters are analyzed by means of simulation. The disaster processes in the networks with redundant system become slow，which permits of longer rescue time to repair the system. It can explain the reason why large-scale disaster events rarely happen in real life.