This study was aimed at obtaining detailed information about the interaction of NaCl salinity and elevated atmospheric CO2 concentration in the halophyte S.salsa, which was irrigated with five different salinity levels under ambient and elevated (530 ppm) CO2. The results show that total soluble sugar concentration was significantly increased by salt-treatments in both leaves and roots, and that the most progressive sugar increments were observed in leaves and roots of S. salsa under the elevated CO2. The Na+ concentration in the leaves and roots increased with the increased NaCl concentration, the K+ accumulation gradually decreaed by increasing salinity levels in leaves and roots. Proline increased in response to salt stress along with incremental NaCl concentration. The GB concentrations of leaves were significantly raised as NaCl levels increased. Electrolyte leakage increased in the leaves of S. salsa grown under NaCl stress. ψs of leaves and roots decreased as the NaCl concentration increase, and that elevated CO2 both had markedly greater effects on ψs of leaves and roots. The osmotic adjustment values ascended with elevated CO2 concentration in both leaves and roots.