Global climate changes characterized by the elevation of CO₂ concentration and temperature will have significant impacts on ecosystems in Northwest China. Warming and elevated atmospheric CO₂ concentration effects have been extensively studied separately; however, their combined impact on plants is not well understood. In this study, we conduct experiments to understand the response of Caragana jubata(Alpine shrub) to the elevated CO₂ (eCO₂) and temperature (eT) using the controlled environmental test. Two different CO₂ concentrations (C₁:400 μmol/mol, C₂:800 μmol/mol) were imposed at two different temperature regimes of 20℃/10℃ and 23℃/13℃ (day/night). The results showed that the effects of eT on the seedling were greater than that of eCO₂. They showed the opposite effects. The total biomass of C. jubata was reduced by eT, and its net assimilation rate (NAR) with relative growth rate (RGR) were decreased too. The eT obviously promoted the above-ground growth, leaf mass ratio, and leaf area ratio. On the contrary, eCO₂ slowed or compensated for the reduction in total biomass, NAR, and RGR. It promoted the growth of under-ground parts of seedling. The activities of superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) were decreased by eT. The antioxidant contents of GSH and ASA were decreased too. eCO₂ increased the SOD activities grown under ambient temperature. It also promoted the overall levels of GSH and ASA. The adverse effects of eT on the antioxidant system of plants were partially mitigated due to eCO₂. In general, the increased temperature and CO₂ did not synergistically promote the growth and photosynthetic capacity of C. jubata seedling. The increase of temperature will greatly affect the growth and antioxidant system of C. jubata. The elevated CO₂ can only partially alleviate these adverse effects by increasing antioxidant levels. Therefore, future climate change, especially the increase in temperature, will have a greater impact on alpine shrub. The elevated CO₂ will alleviate the adverse effects of warming.