Using multi-channel rock- concrete rheological system controlled by a micro-computer, the compression test of concrete sample was carried out to study the deformation and destruction law of concrete sample under different hydraulic pressure and axial load in real water environment. The research shows: the axial strain of concrete sample becomes larger when increasing hydraulic confining pressure in real water environment, high hydraulic pressure goes against strain stability of concrete structure over time; Hydraulic confining pressure can make concrete sample reflecting plasticity to some extent, meanwhile accelerate the damage process of concrete sample when micro cracks are appeared. Because the water has liquidity and fracturing effect, expansibility in concrete microstructure will be produced by hydraulic pressure and break the stability of concrete structure in real water environment. The capability of concrete sample to resist elastic deformation is enhanced, but the capability of concrete sample to resist overall deformation is decreased under hydraulic confining pressure.