Abstract: Recent laboratory studies of the flow and fracture of rocks under general triaxial compression are reviewed .New Developments in laboratory techniques have made it possible to measure three principal stresses and strains under general triaxial stress states ,in which all three principal stresses are different . Strength and ductility of isotropic rocks are markedly affected not only by the least compression σ3 ,although these two effects are rather additional in strength ,but opposite in ductility .The experimental results show that dilatancy is highly anisotropic rocks have been also measured under the general triaxial compression .In this case ,the effect of the intermediate compression markedly depends on the orientations of the weak planes.