Stone brittleness is defined as rock failure without much change in shape. This parameter is one of the most important mechanical properties of rock that is important for safety and economic design in excavation of underground spaces and the extraction of decorative stone.There is currently no standard method for direct measurement of rock brittleness.Therefore, the indirect methods are used for determining the rock brittleness.The purpose of this study was to estimate thebrittleness of some limestone based on geomechanical properties including density, porosity and point load index.The drilling capabilities of samples are also studied based on the concepts of brittleness.According to the experimental data, the two-variable statistical relationships between the brittleness concepts (B1, B2, B3) with geomechanical properties were established and the correlation coefficients between them were determined.The results show that the use of the point load index can provide an appropriate estimation of the concepts of brittleness B2 and B3, while the density and porosity are not.In addition, the studied limestone are in the class of rocks with hard drilling ability.