Abstract: Two-year-old apple trees（Malus × domestica Borkh.‘Red Fuji’）/Malus hupehensis were used to study the effects of six different soil pH treatments（soil pH 6.83，6.40，5.87，5.29，4.58 and 3.82，respectively）on growth and the characteristics of distribution and utilization of carbon and nitrogen using the track technology of ¹³C and ¹⁵N double mark. The results showed that the biomass of root，above ground，total dry weight，root-cap ratio，net photosynthesis and ¹⁵N utilization efficiency decreased with the decrease of soil pH value. The ¹⁵N and ¹³C distribution patternwere consistent in various organs among the different soil pH treatments：Mainly in the leaves，followed by the annual stems，then the roots，and the biennial stems were the least. Differences in the same organ（especially in roots and leaves）in ¹⁵N and ¹³C distribution ratio were found among the different soil pH treatments. With the decrease of soil pH value，the 15N and 13C distribution ratio in leaves increased，while those values in the roots decreased.

Key words: apple, soil pH, growth, 13C, 15N, distribution and utilization