Elastic modulus E，Poisson ratio μ，shear modulus G and fracture toughness KIC of the slates with different stratification angles were obtained by the uniaxial compression tests and relaxation method of double torsion constant displacement load using SANS and MTS-insight testing machines. The relationships among the stratification angle, compressive strength, and fracture toughness were examined. The analysis results show that the uniaxial compression and fracture toughness decrease and then increase with the increase of angle β, which shows a U-shaped relationship curve. When the angle β of the slate is 45°, the fracture toughness is minimized. The crack initiation and crack propagation are developed under the axial load, and the slate is destroyed regardless of c and φ values. Moreover, when the angle β is known, the value of the related fracture toughness can be estimated by using the experimentally derived relationship.