Abstract: Four water stress treatments and 3 inoculation treatments were set up to determine the root morphology, seedling height, biomass, root/shoot ratio of mycorrhizal seedlings. The effects of different mycorrhizal fungi on the growth of Rhododendron amurensis under drought stress were analyzed.Result showed that under normal water conditions, inoculation of ERM significantly increased seedling height, leaf area, and the biomass accumulation of aerial parts and underground parts of seedlings, and promoted the growth of R.annae. Under mild water stress, length and surface area of root and seedling height were higher than those of other treatments. However, with the aggravation of stress, the seedling height and leaf area of CK decreased gradually. The seedling height of mycorrhizal seedlings increased with mild stress, and then decreased. The decrease of mycorrhizal seedling leaf area was less than that of CK. Inoculation of different strains of promoting growth effect was also different. Inoculation TY35 had better mitigation effects than inoculation TY29 on R.annae seedlings under drought stress.