To accurately grasp the failure mechanism of deep rock mass, the large size specimens made by rock-like material were compressed under different biaxial loading rates, and the AE (Acoustic Emission) behavior characteristics of specimens crack propagation were analyzed. Based on plenty of experimental data from previous research, the 425 portland cement, sand with particle size less than 2 mm , gypsum, water-reducer and water were chosen as rock-like material, and optimal proportion of various components was obtained by orthogonal test. Then, the influence law of different biaxial loading rates on crack evolution to large size specimens was analyzed together with its AE behavior characteristics, applying the true triaxial rock test system of coupled stress-seepage and PCI-2 real-time monitoring system of AE. The results showed that the larger loading rate, the much easier anti-wing cracks appeared so that sudden shear failure happened in specimens. However, the AE behavior characteristics of specimen failure under different biaxial loading rates are similar. The cumulative AE events abruptly increase when the load is to 90%σc, showing the cracks transfixionat due to propagation which resulte in specimens fracture.