Abstract: In order to study the effects of salt stress on seed germination and seedling growth of Echinochloa crusgalli, the seed of three Echinochloa crusgalli varities-Mi bai, E toubai and Suo lianbai were taken as the research objects. Three salts, NaCl, NaHCO₃ and Na₂CO₃, were selected as stress treatments for three species of Echinochloa crusgalli seeds, and the concentrations of NaCl and NaHCO₃ were set to 50, 100, 200 and 300 mmol/L, respectively, and the concentrations of Na₂CO₃ were set to 25, 50, 100 and 150 mmol/L, with purified water treatment as the control（CK）. The germination percentage, germination index, seedling length, root length and root-to-crown ratio of three species of Echinochloa crusgalli seeds were determined by using petri dish germination method. The regression equations of germination rate and salt stress concentration of the three species Echinochloa crusgalli were established, and the appropriate concentration value, critical concentration value and ultimate concentration value of the three species Echinochloa crusgalli seeds subjected to different salt stress concentrations were calculated.The results showed that low NaCl concentration（50 mmol/L） could increase the three Echinochloa crusgalli seeds germination rate, seedling length, while high NaCl concentration（200,300 mmol/L） decreased the seed germination rate, germination index and seedling length. NaCl stress decreased the root length of the three Echinochloa crusgalli. NaHCO₃ and Na₂CO₃ stress decreased the germination rate, germination index, seedling length and root length of E toubai and Suo lianbai. Neither Mi bai seed nor E toubai seed germinated when stressed by the max concentration of NaHCO₃ and Na₂CO₃. Under NaCl, NaHCO₃, Na₂CO₃ stress, the appropriate concentration value, critical concentration value and ultimate concentration value of Mi bai were the highest among the three species. It indicated that Mi bai had the strongest salt tolerance among the three Echinochloa crusgalli varities.