Abstract: 【Objective】 Study the growth and physiological changes of American black walnut under salt stress and a comprehensive analysis of the salt tolerance of different seedlings, with a view to providing a reference for the selection and breeding of salt-tolerant varieties of black walnut, salt resistance mechanisms and the screening of salt-tolerant rootstocks in Xinjiang walnut growing areas. 【Methods】 The growth and physiological responses of seedlings of small-fruited black walnut(Juglans regia.microcarpa), northern California black walnut(Juglans regia.hindsii), eastern black walnut(Juglans regia.nigra)and quebracho black walnut(Juglans regia.major)were analyzed by correlation analysis and subordinate function analysisgrowth and physiological responses of above-ground dry weight, below-ground dry weight, main root length, lateral root number and MDA content of the four black walnut seedlings were analyzed. 【Results】 After 40 d of salt stress, above-ground dry weight, below-ground dry weight, main root length and number of lateral roots all decreased to different degrees, with different magnitudes of change for different materials; with increasing salt concentration, malondialdehyde content increased, and SOD activity, POD activity, proline content and soluble sugar content generally showed a trend of first increasing and then decreasing. 【Conclusion】 A comprehensive analysis of the affiliation function values yielded four species of black walnuts in descending order of salt tolerance:eastern black walnut > small-fruited black walnut > quebracho black walnut > northern California black walnut.