Abstract: Using seedlings of Malus baccata, M．xiaojinensis and M．zumi as the experimental materials. Na²⁺ exclusion capability was determined to affirm the whole Na²⁺ exclusion capability, and the whole Na²⁺ exclusion capability of salt-sensitive species was about 65%, middle salt-tolerant species about 8O%, salt-tolerant species about 90%. Na²⁺ exclusion capability of roots and stem base was the main parts of the whole Na²⁺ exclusion capability in Malus seedlings. Na²⁺ exclusion capab ility in roots and stem base of salt-tolerant species was obviously higher than that of salt-sensitive species. Lateral roots．stem base xylem and old leaves of salt-tolerant cuhivar obviously occured Na²⁺ accumulative effect, and were main Na²⁺ accumulative localizations. Through shoot Na²⁺ re-distribution and re-transportation. Na²⁺ content became even less in young leaves an d mature leaves of salt-tolerant species

Key words: Malus, Salt resistance, Sodiumion, Salt stress, NaCl treatment, Na²⁺ exclusion capability