The　construction　of　biomimetic　clustercatalysts　with　metalloenzyme-likeactive　sites　may　open　an　avenue　for　the　challenging　transformationof　greenhouse　gases　(e.g.,　CO2)　to　high-value　chemicals.Cu-enzymes　occur　in　all　three　biological　kingdoms,　with　Cu-Z　clusters　serving　as　representative　reaction　sites　that　catalyzechallenging　transformations.　However,　artificial　Cu　clusters　withanalogous　Cu-Z　structures　and　high　stability　are　still　rare.In　this　work,　we　have　successfully　adopted　a　Ti-9-oxo　nanoringas　an　inorganic　templating　scaffold　to　isolate　a　small　Cu-4　cluster,　which　can　be　regarded　as　a　atomically　precise　bioinspiredcluster　with　metalloenzyme-like　catalytic　sites　(Cu-Z).Importantly,　Cu　(　4　)　@Ti　(　9　)　displays　high　selectivity　for　the　electrocatalyticreduction　of　CO2　to　C2H4　(FE:　47.6　+/-　3.4%)　at　400　mA　cm(-2)　and　good　catalytic　durability(8　h).　The　bioinspired　Cu　(　4　)　@Ti　(　9　)　not　only　represents　the　firstexample　of　Cu　cluster　directly　encapsulated　by　a　metal-oxo　shell　butalso　opens　the　CO2　electroreduction　to　ethylene　applicationsof　atomically　precise　metallic　clusters.