Abstract: In order to give clear definition of weakly cemented sandstone, taking weakly cemented sandstone in Buertai Mine overburden as the research object, th ree kinds of sandstone samples were collected by using the core drilling method. Firstly, the composition and microstructure were analyzed.Secondly, the three kinds of specimens were carried out with uniaxial compression, triaxial compression and Brazil split experiment.Finally, the parameters such as density, wave velocity, tensile str ength, compressive strength, elastic modulus, cohesion and internal friction angle were analyzed. Experimental results show that weakly cemented sandstone is a rock with quartz and feldspar as the skeleton particles.And the cement content is less than 30% of the total content.The pores between the grains of weakly consolidated sa ndstone are very large, mainly concentrated in the 40 ~ 100 um.The cement is very small and the grain boundaries are very clear.The weakly cemented sandstone is m ainly along the boundary of the particle.The macroscopic fracture type is dominated by the' I"type.The wave velocity (