Abstract: With potted Hovenia dulcis and Gleditsia sinensis seedlings as test materials, their plant growth, chlorophyll fluorescence characteristics, and active oxygen metabolism under stress of different concentration (0, 0.15%, 0.30%, 0.45%, and 0.60%) NaCl were studied. The results showed that with increasing concentration of NaCl, the plant growth, leaf chlorophyll content, photochemical efficiency of PSⅡ (F_v/F_m), quantum yield of PSⅡ(Φ_PSⅡ), and photochemical quenching (q_P) decreased gradually, while the non-photochemical quenching of fluorescence (q_N) was in adverse. After 10 days of 0.15% NaCl stress, the leaf chlorophyll content, F_v/F_m, Φ_PSⅡ, and q_P of H. dulcis seedlings decreased by 19.77%, 2.94%, 29.03%, and 8.16%, respectively, with significant differences (P<0.05) to the control, while no significant differences were observed for G. sinensis seedlings. Compared with the control, the F_v/F_m and Φ_PSⅡ of G. sinensis seedlings in treatment 0.30% NaCl decreased significantly by 1.91% and 14.66%, and the chlorophyll content and q_P of the seedling in treatment 0.45% NaCl decreased significantly by 29.28% and 11.36%, respectively (P<0.05). With increasing concentration of NaCl, the SOD activity of G. sinensis seedlings showed a consistent increasing trend, and that of H. dulcis seedlings increased first and decreased then. The POD and CAT activities of G. sinensis and H. dulci seedlings tended to increase first and decrease then, with the increment being higher for G. sinensis than for H. dulci, while the MDA content of the seedlings had an increasing trend, with the increment being higher for H. dulcis than for G. sinensis, suggesting that the cell membrane lipid peroxidation of H. dulcis was more serious than that of G. sinensis. It was concluded that G. sinensis had greater salt tolerance than H. dulcis, which was related to its higher anti-oxidation enzyme activities.