Abstract: Aiming at the acoustic emission behaviors of aplite granite in Portugal,several uniaxil compressive tests with cyclic loadings were carried out on the same rock sample for monitoring acoustic emission activities and recording deformation of rock in order to acquire the relationship between them.It was found that the more the stress exerted on the rock sample,the weaker Kaiser effect became.But in balance,Kaiser effect existed profoundly in aplite granite even when the specimen was under high stress.To determine Kaiser point,using time-cumulative energy curve was easier and more reasonable than using time-cumulative AE events curve,as the inflection point in time-cumulative energy curve was so easy to be obtained.Furthermore,a good understanding on compression-deformation behavior of rock was a beneficial supplement for the explanation of acoustic emission test results.