Failure mechanisms of shallow foundations resting on rock with isolated multiple cavities was studied under uniaxial compressive conditions. Various variables were investigated and those were: rock properties, cavity size, cavity depth, and cavity location. Upper bound mechanism had been derived depending on failure mechanisms obtained from experimental results in this study. One upper bound mechanism was made for circular shallow foundation resting on rock with spherical isolated multiple cavities and this was sidewall failure mechanism. The ultimate collapse pressure estimation equation for shallow foundation resting on rock containing multiple cavities was developed as a function of rock properties, and the geometry of the mechanism. This equation can be used to determine the ultimate bearing capacity of shallow foundation resting on rock with multiple cavities. The results were compared with previous works results. There was a good agreement between results.