The uniaxial compression tests of dry and water-saturated red sandstone containing a single hole are conducted to analyze the characteristics of force and deformation, crack extension mechanism, acoustic emission characteristics and energy evolution based on the TAW-2000 test equipment, camera system and PCI–2 acoustic emission detection analysis system. The results show that the mechanical parameters of water-saturated rock sample are significantly lower than those of dry rock sample while the coefficients of brittle drop significantly increase. Crack propagation process can be divided into four stages: initial deformation stage, crack initiation stage and crack stable propagation stage and crack unstable propagation stage. The initial cracks and secondary cracks of water-saturated rock sample are more and longer, and significant force drop appears when initial cracks generate and cracks propagate unsteadily. The ring counts of rock samples focus on crack initiation and crack unstable propagation stage. In the water-saturated rock sample, the AE signals are less than dry rock sample. The AE signals during crack initiation stage are more than those during crack unstable propagation stage. Compared with the dry rock sample, the external energy is easier to dissipate in the water-saturated rock sample and the energy storage rate is slower to reach the peak. Therefore, the stored elastic energy is less in the water-saturated rock sample, which is more conducive to reducing the intensity of energy release during rock failure.