The as-cast Mg85Ni15-0.2 wt.% Ti and Mg68Ti9Ni23 alloys were produced with vacuum induction levitation melting furnace. The Mg85Ni15-0.2 wt.% Ti alloy had a reversible hydrogen storage capacity of 5.22 wt.% at 653 K. Intersection of hydrogen absorption curves at different temperatures, which could be found during the initial hydrogenation process, indicated two competed kinetic mechanism took part in the original hydrogenation. Pressure-composition isothermal (PCI) curves showed two pressure plateaus for all applied temperatures. The enthalpies, obtained by PCI data, of hydrogenation for these two alloys were estimated to be about 5 kJ/mol lower than MgH2. Results of Kissinger plots, based on DSC data, showed the activation energy of dehydrogenation were 51.69 kJ/mol and 57.75 kJ/mol, which were much lower than pure MgH2, for Mg85Ni15-0.2 wt.% Ti and Mg68Ti9Ni23 alloys, respectively.