Inter-provincial　trade　leads　to　changes　in　CO2　and　air　pollutant　emissions.　However,　there　is　a　research　gap　regarding　the　coordinated　effects　(co-effects)　between　embodied　CO2　and　air　pollutant　emissions　in　trade.　Understanding　co-effects　in　inter-provincial　trade　is　a　prerequisite　for　driving　the　green　transformation　of　trade　and　achieving　coordination　between　pollution　and　carbon　reduction.　Here,　we　calculated　provincial-level　CO2　and　air　pollutant　emission　leakage　in　2012　and　2017　based　on　a　modified　input–output　model　and,　for　the　first　time,　investigated　the　co-effects　between　CO2　and　air　pollutant　emission　leakage　caused　by　emissions　transfers　in　China.　Three　types　of　co-effects,　categorized　as　co-benefits,　trade-offs,　and　co-damage,　were　discovered　and　defined　to　reveal　the　provincial　differences.　Furthermore,　combined　with　structural　decomposition　analysis　(SDA),　we　calculated　the　interannual　variation　in　trade-induced　emissions　and　identified　the　key　driving　factors　of　provincial-level　co-effects　from　2012　to　2017.　Optimizing　the　energy　structure　has　led　to　the　greatest　co-benefits,　while　changes　in　the　industrial　structure　and　emission　coefficients　have　led　to　limited　co-benefits　in　specific　provinces.　Variations　in　trade　volume　have　led　to　co-damages　across　all　provinces,　and　changes　in　emission　coefficients　have　led　to　trade-offs　in　the　majority　of　provinces.　The　case　analysis　confirmed　that　identifying　and　adjusting　the　key　driving　factors　of　co-effects　can　promote　the　transformation　from　co-damage　and　trade-offs　to　co-benefits.　The　findings　implied　a　new　approach　for　the　reduction　in　pollution　and　carbon　through　inter-provincial　trade.　©　2024　by　the　authors.