Abstract: Self-developed point load tester and RMT-150B rock mechanics testing system were used to investigate the point load strength and uniaxial compressive strength of the rock in the roof and floor of coal seam. The results show that irregular rock point load strength basically meets the criteria of Gaussian distribution. Meanwhile, failure load of point load and failure area show a linear relationship. The different failure load areas have no influence on size and shape effect in point load test. By analyzing the relationship between point load strength and uniaxial compressive strength, empirical formula of using point load strength to quickly and accurately determine uniaxial compressive strength is obtained.