This study aims to understand the response of the chemometric characteristics of Artemisia ordosica along with precipitation changes and to elucidate the biological mechanism of productivity maintenance of A.ordosica from the perspective of coordinated nutrient distribution among leaves, so as to provide a basis for predicting the evolution of desert vegetation under the background of climate change. By means of field precipitation control experiments, six precipitation gradients were set, and the productivity of A.ordosica populations and the chemometric parameters of leaves and soils were measured under different precipitation levels. The results showed that: 1) Total Phosphorus content of soil in Artemisia oleifera communities decreased significantly due to leaching when precipitation increased, while soil organic carbon, total nitrogen and total phosphorus contents of soil in Artemisia oleifera woodland did not change when precipitation decreased. The SOC and TN contents of leaves of Artemisia oleifera did not change significantly when precipitation increased, but increased when precipitation decreased, and too much or too little precipitation would reduce the TP contents of leaves. 2) Nutrient content of leaves at different maturity levels responded differently to changes in precipitation. The correlation between mature leaves of Artemisia oleifera and soil stoichiometry was significant, while the correlation between young leaves and soil stoichiometry was not significant. The nutrient content of mature leaves was easily affected by the environment, while the nutrient content of young leaves was more stable. Artemisia oleifera preferentially allocated C and P to the young leaves under the condition of reduced precipitation, choosing to sacrifice mature leaves to maintain the growth of young leaves. 3) The productivity of Artemisia oleifera increased with the increase of precipitation, and the aboveground net primary production of Artemisia oleifera reached the maximum value in the 30% rainfall increment treatment group, but the ANPP decreased in the 50% rainfall increment group, which was related to the loss of nutrients in the soil triggered by excessive precipitation. The correlation between the ANPP and the content of TP in the young leaves was extremely significant, and the correlation between ANPP and the content of each element in the mature leaves was not significant, which can be speculated that, in the context of the change of precipitation, Artemisia oleifera has an intrinsic biological regulation mechanism of nutrients to achieve the growth of young leaves. Thus, it can be inferred that there is an intrinsic biological regulation of nutrients in Artemisia oleifera to achieve the optimal plant productivity under rainfall changes.