uralensis, indicating that low to moderate P addition increased P availability of soils and P uptake of G. uralensis (leaves and roots) and in soils but increased aboveground biomass and root biomass of G. Important findings The results showed that, reducing N:P decreased C:P and N:P ratios both in G. Additionally, through the correlation analyses between biomass and C:N:P ecological stoichiometry in leaves, roots, and soils, we compared the differences among the C:N:P ecological stoichiometry of the three pools, and discussed the indication of C:N:P ecological stoichiometry in soils for the growth and nutrient uptake of G. uralensis (leaves and roots) and in soils. Methods Based on a pot-cultured experiment conducted for Glycyrrhiza uralensis (an N-fixing species) during 2013 to 2014, we studied the effects of different N:P supply ratios (all pots were treated with the same amount of N but with different amounts of P) on aboveground biomass, root biomass, root/shoot ratio, and C:N:P ecological stoichiometry both in G. Studies on the effects of artificial N:P treatment on the growth and carbon (C), N, P ecological stoichiometry of desert steppe species could provide not only a new insight into the forecasting of how the interaction between soils and plants responses to long-term atmospheric N deposition increase, but also a scientific guidance for sustainable management of grassland in northern China under global climate change. Aims The increase in atmospheric nitrogen (N) deposition has accelerated N cycling of ecosystems, probably resulting in increases in phosphorus (P) demand of ecosystems.