In order to reveal the improvement effects of different Ulmus pumila strains on soil salt in coastal saline alkali land and the distribution and absorption characteristics of salt ions in the soil:Ulmus pumila system, and to select the salt tolerant Ulmus pumila strains for afforestation in coastal saline alkali soil, six species of Ulmus pumila (No.1, 5, 28, 30, 46, 105 respectively) with 4 years old under moderate saline habitat were taken as test materials. Through field sampling and lab analysis, the distribution characteristics of salt ions (Na⁺, K⁺, Ca²⁺, Mg²⁺) in roots, stems, leaves of Ulmus pumila and soils were analyzed. The results showed that:(1) Ulmus pumila could significantly reduce the total salt contents of coastal saline alkali land, and the salt contents under different Ulmus pumila strains were 55.0%~63.1% lower than that of the control, Ulmus pumila of No. 30 gave the biggest reduction. (2) All the Ulmus pumila accumulated Na⁺, K⁺, Ca²⁺ and Mg²⁺ preferentially in the leaves, and high K⁺/Na⁺, Ca²⁺/Na⁺ and Mg²⁺/Na⁺ ratios were maintained in leaves. Ulmus pumila could adapt to salt stress by establishing new ionic equilibrium. (3) The absorption selectivity coefficients for all different Ulmus pumila strains were S_K,Na > S_Ca,Na > S_Mg,Na. The absorption selectivity of K⁺ was greater than those of Ca²⁺ and Mg²⁺. Different Ulmus pumila strains had different absorption ability for Na⁺, K⁺, Ca²⁺ and Mg²⁺, among which No. 28 had the highest absorbency to K⁺, And No. 5 had the strongest absorbency to Ca²⁺ and Mg²⁺.