The hydrolysis of lithium bis[1,2-oxalato(2+O,O'] borate (LiBOB) was investigated in pure water and in solutions of acetonitrile at low water content. The reaction in pure water can easily be observed by time-dependent conductivity measurements as protons are generated in the first step of hydrolysis. The results of these measurements can be evaluated according to a reaction of pseudo first order. Hydrolysis of other lithium borates in water was also studied for comparison. In acetonitrile as solvent, hydrolysis is much more complicated. NMR studies show a very slow reaction of LiBOB with water resulting in equilibria, depending on the water content of acetonitrile. Temperatures of 60 degrees C and water contents of several percent are necessary to achieve observable effects.