An experiment with shell sand was carried out to study the effects of NaCl stress on the characteristics of photosynthesis in Limonium bicolor.Five different concentrations of NaCl were applied:0,50,100,200,300 mmol/L for 30 d.The results showed as follows:(1)Under 50,100 mmol/L NaCl stress,the net photosynthesis rate (P_n),instantaneous water use efficiency (WUE),apparent light use efficiency (LUE),carboxylation efficiency (CE),light saturation point (LSP),apparent quantum efficiency (AQY) all reached maximum value,which showed Limonium bicolor has a strong ability to adapt to salt stress and light intensity.The most wide ecological amplitude of light was observed.The minimum of light compensation point (LCP) was observed.(2)P_n,WUE,LUE,CE,LSP and AQY decreased,but LCP increased with NaCl stress being 300 mmol/L.The light response curves of P_n,T_r,G_s,WUE,LUE,CE were different from control significantly,which showed that the higher the NaCl stress was,the more sensitive of characteristics of photosynthesis in L.bicolor were about light density.Its ability to use light intensity decreased.The ecological amplitude of light became narrow.The optimal range of PAR for WUE,LUE,CE is different,which is low PAR,middle PAR,high PAR.WUE has the maximum ability to adapt to salt stress,CE second,LUE minimum.