In order to clarify the mechanism of rockburst, using the specified loading equipment and the CT machine, the real-time computerized tomography testing of coal under the uniaxial compression was completed. Through CT scanning, the clear CT images which included the stage from the microcrack clousre to the microcrack growth, bifurcation, development, failure and the post-failure stage were obtained. According to the CT values, the meso-damage evolution of coal under uniaxial compression was analysed, which provided the basis for the meso-damage evolution.