This study aimed to investigate the acclimation responses of crop hydraulic traits to future climate scenarios and quantify the potential hydraulic risks. Potted maize was acclimated to varying [CO ₂] levels (400, 700, and 1,000 ppm in 2018; 400 and 700 ppm in 2020), while under water deficit (WS) or soil salinity (SS) treatments. Plant growth and hydraulic traits following the acclimation were comprehensively assessed. WS or SS inhibited growth and showed remarkable impacts on maize hydraulic traits. Especially, the water potential that leads to 50% loss of conductivity (P ₅₀) decreased by 1 MPa. When subjected to elevated [CO ₂], the WS and SS plants improved their growth by 7-23%. Meanwhile, elevated [CO ₂] significantly increased xylem vulnerability, resulting in smaller hydraulic safety margins. According to the t _crit plant desiccation model, the critical desiccation degree (time*VPD) plants can tolerate under drought was 43-64% reduced at elevated [CO ₂]. In addition, the sensitivity analysis showed that the P ₅₀ is the most important trait in determining the critical desiccation degree. Our findings demonstrated that while elevated [CO ₂] was beneficial to plant productivity under WS or SS, it interfered with the plant hydraulic acclimation, potentially placing them at a higher risk of hydraulic failure and mortality.