Abstract: The laboratory experiments of rock mechanics, as one of the most effective methods to analyze the mechanical property of rocks, had already used widely by scholars at home and abroad. However, various influence factors, such as experimental instruments, developmental microfissure, porosity and so on, made rock mechanical parameters were different. This paper collected 4, 000m deep drilling in Northwest Shandong Gold Mine, and mainly analyzed the influence of rock mechanical property caused by microfissure, porosity ratio, surrounding rock and fiction of rock sample tested. The analysis based on the results of split test, axial tests and triaxial tests, combined with the fracture orientation, the way of failure and strength character. The results of this study could provide theoretical basis for rock mechanics tests.