Abstract: With the controlled experiment and different gradients of salt stress，the characters of growth and physiological biochemistry of cutting seedling of 9 clones of Catalpa bungei were studied under 6 salinity(NaCl) treatments，the salinity content was 0，1，2，2.5，3 and 4 g/kg of soil dry weight，respectively．Salt tolerance of 9 clones of C. bungei were evaluated by the fuzzy subordination methods．The results showed that growth rate of seedling height and root collar diameter were significantly influenced by salt stress and effect on the former was obvious．The chlorophyll content decreased with the increase of NaCl concentration in all clones，while relative conductivity increased．SOD activities，proline and soluble sugar contents increased first and then decreased with the increase of sale stress in clones of 02-2-5,14-6 and YQ1．While the 3 characters had great difference among other clones．According to analysis of membership function of fuzzy mathematics method to the 9 clones，the salt tolerance was in the order of 02-2-5, 9-1, 14-6, YQ1, 1-3-36, 02,2-2-3,02-2-2,07-1.