Abstract: Using the triaxial rock mechanics testing unit manufactured by American MTS Co, rock strength and deformation behavior are studied. The test results of core specimens show that rocks with the same lithologic properties indicate different deforming behavior while rocks with different lithologic properties similar curves of stress vs. strain due to the influence of weakness planes and filling on the rock, considering the influence of rock nonlinearity, reservoir condition and rock structure behavior, it is necessary to treat the test results based on the study range.