Responses of seed germination of 4 desert vegetation species﹝Zygophyllum xanthoxylum Bunge.,Ammopiptanthus mongolicus(Maxim.)Cheng f.,Reaumuria trigyna Maxim,and Amygealus mongolica Maxim﹞to soil moisture were studied.Results showed that soil moisture had a significant effect on the seed germination and seedling growth.At 6% soil moisture content,germination rate and germination index of Z.xanthoxylum seeds reached peak value,vigor index and seeding biomass were the greatest,and seedlings of Z.xanthoxylum grew well.Germination and growth of A.mongolicus seeds behaved very well at 12% soil moisture content and those of R.trigyna and P.mongolica seeds behaved also well at 16% soil moisture content.The seed germination strategy of the 4 plants reflects different adaptation mechanisms to desert moisture condition and affects population regeneration and expansion.