Using artificial experiment, the "fertilization function" of CO₂ enrichment on Aneurolepidium chinensis and Stipa baicalensis is analyzed.The results showed that the biomass increased with CO₂ concentration enrichment, and their total biomass increased by 40.0% and 45.0%.The impacts of soil drought on growth and accumulation of dry matter of Aneurolepidium chinensis and Stipa baicalensis were negative, and these negative impacts were enhanced with drought aggravating.Total biomass decreased by about 16% and 30% under light drought, and decreased by about 44% and 35% under heavy drought.The fertilization effect on the two species weakened under soil drought, and it was more obvious on Aneurolepidium chinensis than on Stipa baicalensis.