In this study, the hydrogen storage properties of MgH2 with the addition of K2TiF6 were investigated for the first time. The temperature-programmed desorption results showed that the addition of 10 wt% K2TiF6 to the MgH2 exhibited a lower onset desorption temperature of 245 degrees C, which was a decrease of about 105 degrees C and 205 degrees C compared with the as-milled and as-received MgH2, respectively. The dehydrogenation and rehydrogenation kinetics of 10 wt% K2TiF6-doped MgH2 were also significantly improved compared to the undoped MgH2. The results of the Arrhenius plot showed that the activation energy for the hydrogen desorption of MgH2 was reduced from 164 kJ/mol to 132 kJ/mol after the addition of 10 wt% K2TiF6. Meanwhile, the X-ray diffraction analysis showed the formation of a new phase of potassium hydride and titanium hydride together with magnesium fluoride and titanium in the doped MgH2 after the dehydrogenation and rehydrogenation process. It is reasonable to conclude that the K2TiF6 additive doped with MgH2 played a catalytic role through the formation of active species of KH, TiH2, MgF2 and Ti during the ball milling or heating process. It is therefore proposed that this newly developed product works as a real catalyst for improving the hydrogen sorption properties of MgH2. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.