Abstract:A greenhouse experiment was conducted to study the photosynthesis physiological characteristics of Dalbergia odorifera seedlings under water stress.Four treatments were arranged:control(CK),light water stress(LS),moderate water stress(MS) and heavy water stress(HS).The results showed that:(1)Total chlorophyll content of seedlings decreased with the drought stress increased.(2)The net photosynthetic rate,stomatal conductance,intercellular CO2 concentration and transpiration increased under light drought stress and decreased under heavy drought stress.The stomatal conductance and intercellular CO2 concentration decreased together at moderate water stress and heavy water stress,which indicated that the decline of photosynthetic capacity was caused by stomatal restriction.(3)The leaf membrane permeability,MDA content,proline content and POD activity increased with the drought stress increased,SOD and CAT activities were tended to increase and then decrease.The protective enzyme activities increased at moderate water stress while decreased at heavy water stress which indicated that drought tolerance of D.odorifera seedlings was limited.