In this paper, activated aluminum powder was prepared by magnetic grinding with a homemade equipment and hydrolyzed in alkaline solution to produce hydrogen. The results showed that the prepared aluminum powder could improve hydrolysis reactivity effectively and have high hydrogen yield in alkaline solution (up to 1340 mL/g). It was found that grinding time, reaction temperature and grinding media could significantly affect the hydrolysis reaction while alloy components had little effect. Aluminum powder ground for 40 min can produce hydrogen 1340 mL/g within 6 min under optimal reaction temperature of 323 K. Copyright (c) 2013 John Wiley & Sons, Ltd.