Abstract: Effects of two phenolic compounds（p-hydroxybenzoic acid and coumarin）on growth and pivotal respiratory indicators were studied using Cerasus sachalinensis Kom. seedlings as materials. The results showed that the growth of C. sachalinensis seedlings was highly promoted by low concentration of coumarin，and which also enhanced the PSⅡ maximum photochemical efficiency，respiratory substrate content，pyruvate content of metabolic intermediates and MDH activity. However，the key enzyme activities of EMP and PPP were not affected. Coumarin at high concentrations showed inhibitions to seedlings，while brought the PSⅡ maximum photochemical efficiency，starch contents，IDH activities and PFK activities down. p-hydroxybenzoic acid and the mixed solution of the two compounds at the 3 testing concentrations（0.1，1.0 and 10 mmol · L-1） both restrained seedling growth at certain extent. Contents of citric acid were reduced and key enzyme activities of PPP were improved. The PSⅡ maximum photochemical efficiency and respiratory substrate content were not changed by low concentration of p-hydroxybenzoic acid. However，pyruvate content，HK，PK，SDH activities were promoted. On the contrary，IDH，MDH activities were lowered. p-hydroxybenzoic acid at high concentrations showed suppressions on PSⅡmaximum photochemical efficiency，respiratory substrate contents，respiratory intermediates contents，and PFK，PK，IDH，MDH activities，but enhancement on HK activity.

Key words: Cerasus sachalinensis, phenolic compounds, respiration, growth, key enzyme