Propane dehydrogenation on Pt–Sn/Al 2 O 3 and Pt–Sn/ZnAl 2 O 4 was performed, and the Pt–Sn/ZnAl 2 O 4 catalyst showed a stronger tolerance for catalytic deactivation than the Pt–Sn/Al 2 O 3 catalyst. In this study, we propose that the high catalytic stability of Pt–Sn/ZnAl 2 O 4 originates from the relatively faster coke mobility from the metal surface to the support, which was proven by XPS measurement. XRD and HRTEM associated with EDX demonstrated that Pt–Sn alloy phases over the catalysts were transformed during the reaction and that the bimetallic phase transition was different according to the supports. Both PtSn and Pt 3 Sn alloys were formed on the reduced Pt–Sn/Al 2 O 3 , while only the PtSn alloy was observed on the reduced Pt–Sn/ZnAl 2 O 4 . The Pt 3 Sn phase was dominant over the spent Pt–Sn/Al 2 O 3 , whereas the PtSn phase remained unchanged over the spent Pt–Sn/ZnAl 2 O 4 after reactions for 160 and 240min. The different bimetallic alloy formations and phase transitions in the Pt–Sn catalysts cause different coke mobilities.