Using the replacement series experiments designed by de Wit, the effects of different concentrations(0, 50, 100, 200, 400 mmol/L) of neutral salt(NaCl) and alkaline salt(Na2CO3) on the morphological structure, physiological characteristics and competitiveness of the invasive plant Aegilops tauschii were investigated. The results showed that the growth of both A.tauschii and wheat were inhibited by salt stress, and caused a decrease in plant height, leaf area and total biomass of the two studied plants. Both A. tauschii and wheat adapted to the salt stress environment through increasing SOD activity and proline content. However, as the salt stress was exacerbated, the relative conductivity and thiobarbituric acid(TBARS) content significantly increased of both the two studied plants, which indicated that the salt stress caused a continually aggravating damage to plant cell membrane. Salt stress also caused a decrease in chlorophyll content of the two studied plants. As suggested by the level of increase in SOD activity and the other five physiological indicators, A. tauschii was more tolerant to the salt stress, while the damage degree of Na2CO3 to the two studied plants were greater than those of NaCl. As shown by the CB value, A. tauschii was more competitive than wheat even under salt stress. All together, A. tauschii was showed more tolerant of the salt stress than wheat through the favorable adjustment of morphology, biomass allocation pattern and physiological features, indicating A. tauschii was a superior variety to wheat under salt stress conditions.