Abstract: A large number of experiments, research on the effects of regular cracks to macro-mechanical properties in rock like materials, such as high strength gypsum and white cement, under uniaxial compression are conducted. The experimental relationships of the macro-equivalent strength σ_e, elastic modulus E_e and passion's ratio μ_e versus the inclined angle of cracks α are obtained. The specificity curve of σ_e-α, also depending on cracks density h, for multi-crack body is given by the analysis of experimental and theoretical results. The data and conclusion will be useful for mining industry and some other underground engineering.