Rainfall is one of key factors influencing plant functional traits and ecosystem function in desert regions. Under the situation of global warming, the precipitation in desert areas of China shows an increasing trend, but the response characteristics of plant and soil stoichiometric trait to precipitation in these areas are not clear. In this study, Nitraria tangutorum shrub in UlanBuh Desert was selected as the research object to conduct precipitation enhancement experiment to explore the effect of long-term rainfall enhancement on plant leaves and soil eco stoichiometry. A rainfall manipulation experiment was conducted from 2008 to 2022, with four enhancement precipitation and one CK treatments: natural precipitation (R0, CK) and rainfall increases of 25% (R1), 50% (R2), 75% (R3), and 100% (R4). The results showed that: 1) rainfall enhancement could significantly increased the content of TC and TP in N. tangutorum leaves (P<0.05), and with the increase of rainfall intensity, the content of TN in leaves showed a pattern of decreasing firstly and then increasing. Under R1 treatment, the C/P and N/P of N. tangutorum leaves reached the minimum, which were 35.79% and 38.49% lower than those under R0 treatment, respectively (P<0.05); 2) Rainfall increased the element content and stoichiometric ratio of topsoil significantly. AP content in 0-2 cm soil layer and C/P and N/P in 2-10 cm soil layer reached the maximum in R4 treatment, which increased by 58.21%, 31.46% and 70.56% respectively compared with R0 treatment (P<0.05); 3) Soil N/P and pH were the main factors affecting the stoichiometric trait of N. tangutorum leaves under rainfall enhancement treatments. In addition, the response of leaf TC content of N. tangutorum to meteorological factors was the strongest, which F value is 4.288. The leaf TC, TN, TP and N/P of N. tangutorum were mainly affected by air humidity, and the C/N and C/P were mainly affected by surface temperature. These results provide a long-term rainfall enhancement test case of plant ecosystem in desert area and also have important guiding significance under the situation of climate change.