According to the historical data of typhoon disasters in county regions from 2000 to 2016, a number of assessment indicators have been selected, including disaster affected population, death toll, the number of toppled and damaged houses, disaster affected crop areas, and direct economic loss. On the basis of grading these factors, an assessment index of typhoon-induced disasters in China at county level is established using grey relational analysis method, and the typhoon disasters in the selected cities and counties are graded and assessed. The results show that the indicators selected can provide comparative analysis of the extent of varied typhoon disasters and typhoon disasters in different cities and counties, making the index valuable for practical application. According to the grade distribution statistics, cities and counties in the southeast coast of China are prone to typhoon disasters, and cities and counties in Zhejiang Province, Guangdong Province, and Fujian Province are prone to serious (severe and extremely severe) disasters. Serious disasters are more likely to happen in August and September. Taking Typhoon DAMREY (2012) and SOUDELOR (2015), which are of different landing sites and ranges of influence, as examples, the reasonableness of disaster assessment is verified.