Abstract: In order to screen out high-quality forage grass that could adapt to low temperature and drought conditions, four Elymus L. seeds（including Elymus nutans ‘Baqing’, Elymus nutans Griseb., Elymus dahuricus, Elymus sibiricus） were selected in this experiment.Polyethylene glycol-6000（PEG-6000） solution（10%, 20%, 30%） and light incubator were used for drought stress, low temperature（5,10,15 ℃） stress in the incubator, and two factor interaction stress, with a total of 16 treatments. At the same time, 20 ℃ and purified water were used as controls. Each treatment was repeated three times, with 50 seeds in each replicate. After the experiment, the germination rate, germination potential, germination index, vigor index, root length and bud length of four kinds of Elymus L. seeds were counted, and the tolerance of four kinds of Elymus L. seeds to low temperature and drought during germination was comprehensively analyzed by membership function method. The results showed that with the increase of drought stress and the decrease of temperature, the germination rate, germination potential, germination index, vigor index, root length and shoot length of the four Elymus L. seeds showed a downward trend. The seeds of four Elymus L. species could not germinate under low temperature（5 ℃） stress. When the temperature was 10, 15, 20 ℃, and the concentration of PEG-6000 was 10% and 20%, the germination rate, germination potential, germination index, vigor index, root length and bud length of the four Elymus L. seeds were significantly lower than those in the control（P＜0.05）. When the concentration of PEG-6000 solution was 30%, only a small amount of forage seeds germinated at 20 ℃, and there were no signs of forage seeds germinated at 15 ℃ and 10 ℃. According to the membership function analysis, the cold resistance and drought resistance of the tested materials in the germination stage were in the order of Elymus nutans ‘Baqing’＞ Elymus nutans Griseb. ＞ Elymus dahuricus ＞ Elymus sibiricus. The results indicated that Elymus nutans ‘Baqing’ was suitable for spreading in low temperature and arid areas.