We studied the effects of light(continuous light,12 h light/12 h dark,and continuous dark),temperature(10/15 ℃,15/20 ℃,20/25 ℃,25/30 ℃,30/35 ℃,and 35/40 ℃),drought(0,-0.1,-0.2,-0.4,-0.6,-0.8,-1.0,-1.2,-1.4,and -1.6 MPa)and salt(0,0.05,0.10,0.20,0.30,0.40,0.60,and 0.80 mol/L)stress conditions on the seed germination of Populus euphratica,aims to reveal the seed germination sensibility of P.euphratica towards different temperature,light,salt and drought stresses,and reveal the ecological adaptation mechanisms of P.euphratica seed germination.The results showed that:(1)P.euphratica seeds germinated under variable temperature(10 ℃/15 ℃~30 ℃/35 ℃)and three different light conditions(continuous light,continuous darkness and 12 h light/12 h dark),their final germination percentage were more than 77%.The optimum temperature range among three light conditions were 25 ℃/30 ℃ to 30 ℃/35 ℃,and the seeds germinated rapidly and intensively,and three light conditions had no significant effect on seed germination.(2)P.euphratica seeds could germinated under the osmotic stress from -1.4 to 0 MPa,and there was no significant differences among osmotic stress treatments range from -1.0 to 0 MPa,with higher final germination rates,which was more than 90%.However,the seed germination process and germination rate were affected significantly under osmotic stress less than -0.4 MPa,and when osmotic stress less than -1.2 MPa,seed germination was significantly inhibited.(3)P.euphratica seeds could germinated in 0～0.80 mol/L NaCl solution,while the seed germination rates and final germination percentage of P.euphratica saw a decreasing trend along with the increasing salt concentration from 0 to 0.80 mol/L,there was no significant difference in treatments of 0 to 0.20 mol/L.Seeds germination rates,seed germination process and germination ratio were affected significantly when salt solution concentrations were higher than 0.2 mol/L.The results demonstrated that P.euphratica seeds germination characteristics of a broad germination temperature,without strict requirements of light,germinated quickly and intensively under optimum temperatures,and tolerance of salt and drought stresses could help seeds germination quickly under limits of water resource.There was an important ecological adaptation of P.euphratica seed germination to regeneration in arid desert.