The hydrolysis process of NaBH₄ using mixed catalyst Co₂B/Pr₆O₁₁ was studied by drainage method. The effects of the ratios of Co₂B to Pr₆O₁₁ and amount of mixed catalyst Co₂B/Pr₆O₁₁ on the amount of hydrogen release of NaBH₄ are very obvious. When the doping amount is varied between 1-6%, the hydrogen desorption rate of doped samples increasesSfirstlySandSthenSdecreases with the doping amount increases. Comparatively, the effect rule of the amount and the ratio of mixed catalyst Co₂B / Pr₆O₁₁ on the hydrogen desorption amount of NaBH₄ is not obvious. However, after NaBH₄ is being catalyzed by the mixed catalyst Co₂B / Pr₆O₁₁, the hydrogen desorption amount of the sample is obviously changed and the hydrogen desorption amounts of most samples are between 410-525ml. In all samples, the sample doped with 4% 70%Co₂B/30% Pr₆O₁₁ has the maximum hydrogen desorption rate for 540ml/min and the maximum hydrogen desorption amount for 540ml.