Abstract: The ecological services valuation method is adopted to calculate variation of the ecological services value of the forestry in the Yili River basin before and after it was built into a forestry ecological sci-tech demonstration zone.Results show that the ecological services value was 64.0×10⁴ yuan·a-1 before grassland degradation,and dropped to 45.9×10⁴ yuan·a^-1 in 2003 owing to over-loading and over-grazing in the past decades.However,after the establishment of the demonstration zone,it soared up in 2006,being 64.5% over that before the grassland was degraded,and 129.2 % over that in 2003.The increment was mainly attributed to improved indirect ecological services value.Obviously the construction of the demonstration zone has greatly raised the ecological services value of the Yili River basin,and its ecological economic benefits are significant.