The　preparation　of　Co-based　catalysts　with　a　single,　highly　dispersed　active　site　is　challenging　and　crucial　for　the　high-performance　propane　dehydrogenation　(PDH)　owing　to　harsh　reaction　conditions.　Herein,　the　synergetic　strategies　including　catalyst　hydrothermal　treatment　and　CO2　introduction　are　adopted　to　realize　the　highly　dispersed　and　stable　T-d-Co(II)　site　and　applied　for　PDH.　According　to　systematic　characterizations　and　catalytic　performance　evaluation,　the　facial　hydrothermal　treatment　improves　the　C3H6　formation　rate　from　456　to　771　mmol　C3H6　g(Co)(-1)　h(-1)　and　catalyst　stability　via　the　transformation　of　Co3O4　species　to　the　T-d-Co(II)　species.　Meanwhile,　the　further　introduction　of　CO2　into　the　PDH　system　as　a　protective　reagent　for　Co　state　would　facilitate　PDH　with　superior　catalytic　performance　with　TOF　of　700　h(-1)　and　C3H6　formation　rate　of　970　mmol　C3H6　g(Co)(-1)　h(-1).　It　is　revealed　that　the　introduction　of　CO2　maintains　Co　state　with　the　T-d-Co(II)　species　via　inhabiting　the　generation　of　metallic　Co　spices.