The dehydrogenation properties of NaAlH4 doped with Ag2SO4, SrCO3, TiO2 and ZnO were studied by PCT (pressure-content-temperature) and XRD. The results indicate that NaAlH4 doped with TiO2 presents the largest amount of hydrogen release, comparatively, the sample doped with SrCO3 presents the least amount of hydrogen release. Compared to the rate of hydrogen release of all doped samples in the first stage, NaAlH4 doped with TiO2 shows the maximum rate of hydrogen release. In addition, all of the doped samples display an obvious two-stage dehydrogenation in the whole process of hydrogen release, and it is obvious that the dehydrogenation rate in the first stage is faster than that in the second stage. The results from XRD patterns prove that 30 min ball-milling does not cause any structure change and new phase appearing.