The effects of temperature and the concentrations of NaBH 4 , NaBO 2 and NaOH on the rate of NaBH 4 hydrolysis over carbon supported ruthenium catalyst were investigated using isothermal rate data extracted from non-isothermal reactions. It was shown that the hydrolysis was a zero-order reaction with respect to the concentration of NaBH 4 and the reaction rate decreased with the increase of OH -concentration. A rate expression was then derived to correlate the hydrolysis rate with the temperature and NaOH concentration.