The assessment of disaster ecological risk was investigated using remote sensing images of Dongshan Island in China, from 1994, 2003, and 2011. It selected rainstorm and gale as major disaster. Based on the characteristics of rainstorm and gale disasters and regional characteristics of Dongshan Island, it established ecological risk indices from disaster vulnerability, disaster bearing capacity and disaster restoring force. The results showed that the spatial pattern of rainstorm and gale disaster ecological risk appeared obvious change with time; overall, the risk value of low mountain area which is forested in the northwest of Dongshan Island was low, the risk values of northeastern area which is mainly towns and coastal area were high. It was found that human interference during the 17-year period has had both positive and negative effects. Long-term ecological construction in the low mountain area of northwestern Dongshan Island has made this area be forested and has reduced ecological vulnerability, and the overall ecological environment and anti-disaster capability in this area have improved. However, economic development in the form of tourism, aquaculture, and real estate, in conjunction with poor growth of the protective coastal forest, has increased the risk of town area and the coastal area of Dongshan Island. As a result, this paper thinks that this evaluation method not only determines the disaster-bearing capacity and anti-disaster capability of regional ecological systems, but also it can provide scientific advice to regional government departments on disaster management and prevention.