Zeolitic　imidazolate　framework　(ZIF-8)-derived　single-atom　catalysts　(SACs)　are　widely　studied　in　many　catalytic　reactions　such　as　hydrogen　evolution　reaction　(HER),　oxygen　reduction　reaction　(ORR),　and　CO2　reduction　reactions　(CO2RR).　Grinding　procedures　involved　in　the　synthesis　of　ZIF-8-derived　SACs　could　affect　the　catalytic　performance　but　are　less　evaluated　in　the　literature.　Herein,　a　series　of　ZIF-8-derived　cobalt　SACs　(C-Co-ZIFs)　with　different　grinding　processes　to　investigate　the　impact　of　the　grinding　degrees　on　the　performance　of　the　electrochemical　reduction　reaction　of　CO2　(ECO2RR)　is　presented.　The　moderate　grinding　process　affords　a　boost　in　CO　Faradaic　efficiency　(FE,　around　15%　higher　than　that　of　the　original　C-Co-ZIF)　and　the　highest　current　densities　among　all　the　samples.　The　variations　in　the　electronic　structure　of　the　Co　active　sites　in　the　ground　catalysts　are　confirmed　by　X-Ray　absorption　spectroscopy　(XAS)　and　X-Ray　emission　spectroscopy　(XES)　for　improved　catalytic　performance.　The　increased　micropores　in　the　moderately　ground　catalyst　provide　more　exposed　active　sites　while　the　increased　meso-　and　macropores　promote　the　mass　transfer,　benefiting　the　ECO2RR　performance.　It　suggests　that　the　impact　of　grinding　processes　on　the　synthesis　of　ZIF-8-derived　SACs　should　be　considered　for　the　evaluation　of　the　catalytic　performance.