The present provides methods for assessing comprehensive risk of drought and flood disasters on apple. The method adopts an optimal curve relationship between an apple yield reduction rate and drought and flood indexes and considers two disasters of drought and flood at the same time to determine the weather index threshold value under the threshold values of different yield reduction rates, meanwhile, builds comprehensive risk index models of drought and flood disasters from risk of disaster-causing factor, sensitivity of disaster-pregnant environment, vulnerability of disaster-bearing body, etc. using terrain, rivers, vegetation, apple planting area, and water profit and loss ratio, etc., and determine a premium rate according to a level of disaster risk to obtain insurance rates and premiums in different regions according to local conditions, thereby formulating a design scheme of insurance products suitable for local conditions, which has great advantages compared with a traditional single-disaster weather index insurance.