Abstract: At present, most of the researches on ecological compensation standard of hydropower development are based on the estimation of ecological service values and opportunity costs, while neglect the compensation ability and willingness of the compensation subject. This paper introduced the ecological compensation coefficient to characterize the compensation ability and willingness of the compensation subject and modifies the basic value in compensation standard. The compensation value is mainly determined by the external value of hydropower development and the compensation coefficient is determined according to the comprehensive development index of compensation subject calculated by the similarity measurement theory of Vague set. This paper takes Baihetan Hydropower Station and its main beneficiary Liangshan Prefecture as an example to quantitatively study the ecological compensation standard. The calculation results showed that the positive and negative external value of Baihetan Hydropower Station were 144.78 million and 491 million yuan respectively, the compensation coefficient was 0.363, and the compensation standard threshold was ［50.77,139.87］. This study can provide new ideas for the quantification of compensation capacity and willingness in ecological compensation.