More and more engineers apply AE (Acoustic Emission) to research rock fracture and damage. Infrasonic wave could be used to forecast earthquake, and structure earthquake is almost caused by rock compression damage, so in the course of rock fracture and damage, the infrasound wave emission could be researched in order to forecast earthquake. The granite specimens are compressed to damage. The infrasonic information in the course of compression are detected and collected. By means of data analysis, some principles of rock compression damage are found.