Key ecological function areas are the areas that keep ecological balance,lighten natural calamities,and ensure ecological security in region and even in the country.Due to the neglect of protection in the past,key ecological function areas have suffered destroy gravely,and counteracted sustainable development in the regions.Our country pays more attention to the key ecological function areas,and puts forward a series of protection methods to reinforce protection in the areas.There are many ecosystem services of the key ecological function area,but leading ecosystem service is the main aspect of protection.Moreover,leading ecosystem service deeply concerns with the benefit inside and outside the key ecological function area.Accordingly,valuation of leading ecosystem service may become ecological compensation standard in the key ecological function areas.The paper analyzed leading ecosystem service of Ruoergai based on the above discussion,and put forward the ecological compensation standard in theory.