Suppressing irreversible catalyst deactivation is very important in heterogeneous catalysis. In particular, deactivation via sintering of active sites is a significant issue for reactions involving harsh reaction/regeneration conditions. In the present work, we developed a PtGa/γ-Al2O3 alkane dehydrogenation catalyst with exceptionally high activity, selectivity, and long-term stability by markedly suppressing Pt sintering under harsh conditions (reaction/regeneration at ＞823 K). To stabilize Pt, physical and chemical stabilization strategies were synergistically combined. For the former, Pt was introduced during the synthesis of γ-Al2O3 via sol-gel chemistry, which can increase the interfacial contact between Pt and γ-Al2O3 due to the partial entrapment of Pt in γ-Al2O3. For the latter, Ce was doped on γ-Al2O3, which can stabilize Pt via strong Pt-O-Ce bond formation.