Abstract: In order to investigate allelopathic effect of phenolic acids on the growth of bamboo, effects of phenolic acids at different concentrations on Phyllostachys edulis seedlings were studied by potted experiment. Rate of photosynthesis, chlorophyll content, amount of overground and underground biomass, amount of tillering and rhizogenesis of seedlings were determined. The results indicated that growth of Phyllostachys edulis seedlings were inhibited by different concentrations of phenolic acids and their mixture, and the inhibition effect was increased along with the increase of solution concentration. Four kinds of the solution of phenolic acids and their mixture had significant and extremely significant effect on rate of photosynthesis. Highconcentration of 4 kinds of the solution of phenolic acids and their mixture reduced the chlorophyll of seedlings. The solution of ρcoumaric acid, ferulic acid, ρhydroxybenzoic acid at 250 mg/L all had significant effect on the stem amount of seedlings. The solution of 4 kinds of phenolic acids and their mixture at 500 mg/L all had significant effect on the leaves amount and biomass of above portion of seedlings. The solution of 4 kinds of phenolic acids and their mixture at 1 000 mg/L all had significant effect on the stem height and root amount of seedlings. The solution of ρcoumaric acid, ferulic acid, ρhydroxybenzoic acid and mixture of phenolic acids at 1 000 mg/L all had significant effect on the root length of seedlings. The solution of ferulic acid, ρhydroxybenzoic acid and mixture of phenolic acids at 2 000 mg/L all had significant effect on the biomass of underground portion of seedlings. In general, high concentration of phenolic acids accumulated in soil by covering might have inhibition effect on bamboo growth, which might be one of the reasons to bamboo forest declining.