Catalysts with 2.5 wt% Ni supported on MgO-Al2O3 were developed for CH4 dry reform-ing (DRM) that are stable at either mild (stoichiometric) or severe (CH4-rich) conditions. Solid materials were characterized with suitable methods. Catalysts with NiO-MgO-Al2O3 solid solution were active even at 500 °C. In stoichiometric DRM, Ni catalyst modified with La and citric acid reduced both Ni re-oxidation and agglomeration, preserving high activity over 160 h. Besides, proper support pre-treatment or adding Gd3+ both offered outstandingly coking-resistant Ni-based catalysts for CH4-rich DRM over 100 h.