Abstract: Water diversion project shelterbelt has the ecological functions of carbon fixation and oxygen release, soil fixation and fertilizer conservation, leisure and recreation, and can produce remarkable ecological and environmental benefits. Based on the theory of Costanza and MA, the evaluation index system of ecological and environmental benefit of shelterbelt for water division project covering 15 indexes was constructed comprehensively and systematically. The application of value evaluation method was analyzed in detail, and the shelterbelt of main canal of Zhengzhou section of middle line of South-to-north Water Division Project was taken as a typical example. The results showed that the annual ecological and environmental benefit of the shelterbelt was 53,676,700 yuan/a, the annual cost was 8,054,200 yuan/a, and the annual net ecological and environmental benefit was 4,562,500 yuan /a. Among them, the air purification, soil fixation and water regulation are the hot ecological functions of shelterbelt in Zhengzhou section of middle line, rate of contribution are 19.22%, 12.36% and 12.13%, respectively.