Abstract:The experiment was conducted with 7-year-old ‘Hongdeng’ and‘Zaohongbaoshi’ sweetcherry (Prunus avium L. ) trees, and effects of p lant growth regulators on the content of phenolics and relate enzymes activity and rate of germination were analyzed and studied. Results showed that the effects of different plant growth regulators were different: ABA p romoted the accumulation of phenolics 6-BA and GA3 postponed the accumulation of phenolics in the primary stage; In the middle stage, ABA kep t the content of phenolics high while 6-BA and GA3 promoted the content of phenolics peak then it dropped; In the last period, ABA postponed the drop of the phenolics content, 6-BA and GA3 were contrary to ABA. The effect of CA3 was better than that of ABA. ABA made PAL activity raise, and dropped the PPO activity; 6-BA and GA3 made PAL dropped but raised the PPO activity. Effects of different plant growth regulators on the germination rate were different in different periods of dormancy. In the primary stage, 6-BA and GA3 on the rate of germination were not obvious; In the middle stage, 6-BA and GA3 can break dormancy and made the rate of germination more than 50%; In the last period, effects of 6-BA and GA3 were similar to the middle of stage. In the whole period of dormancy, ABA made the rate of germination lowerd and inhibited the dormancy-release.