The phase relations and hydrogenation characteristics of the SrAl_2-xNi_x (0 ≤ x < 0.5) alloys were studied in this paper. All the alloys were prepared by induction melting of appropriate amounts of pure metals. The crystal structures of the alloys before and after hydrogenation were characterized by X-ray diffraction (XRD). The alloy consisted of a single Zintl phase of SrAl₂ when x = 0. However, partial substitution of Al by Ni resulted in multiphase structures of the alloys. When x = 0.1, the alloy was composed of SrAl₂, Sr₅Al₉, SrAl and AlNi phases. With the increase of x, the amount of SrAl₂ and Sr₅Al₉ phases decreased, while the amount of SrAl and AlNi phases increased. Hydrogenation measurements were made at 473K under 3 MPa hydrogen pressure. It was interesting to found that the hydriding kinetics of the Zintl phase alloy SrAl₂ was improved greatly after Ni substitution, whereas the maximum hydrogen absorption capacity decreased. XRD analysis showed that a certain amount of SrH₂ existed in the Ni-substituted alloys after hydrogenation. We believe that the existence of AlNi phase is responsible for the improvement of the hydriding kinetics of the alloys.