Quantifying　the　environmental　impacts　of　a　household　waste-sorting　policy　on　the　household　waste　management　system,　including　collection,　transportation,　and　treatment,　is　the　basis　for　evaluating　the　policy＇s　effectiveness.　Beijing,　the　capital　of　China,　began　to　implement　the　mandatory　domestic　waste-sorting　policy　in　May　2020.　In　this　study,　we　aimed　to　evaluate　the　environmental　impacts　of　the　household　waste　management　system　in　Beijing　before　and　after　implementing　the　sorting　policy　using　the　life　cycle　assessment　method.　Implementing　the　policy　at　the　waste　collection　stage　reduced　the　environmental　impacts　by　minimizing　the　number　of　garbage　bins　consumed　through　their　removal　and　consolidation.　At　the　transportation　stage,　implementing　the　policy　increased　the　environmental　impacts　per　unit　of　waste　via　transportation　structure　changes.　However,　the　overall　impact　was　reduced　because　more　recyclable　materials　were　separated　after　waste　sorting.　The　environmental　impacts　were　reduced　after　implementing　the　policy　at　the　treatment　stage　mainly　because　of　the　change　in　waste　composition　and　the　decrease　in　the　total　volume　of　treatment.　Global　warming　potential　(GWP)　was　the　main　contributor　to　the　environmental　impacts.　After　waste　sorting,　the　GWP　of　the　collection,　transportation,　and　treatment　stages　decreased　by　-19.96%,　-24.36%,　and　-38.08%,　respectively,　resulting　in　a　total　GWP　reduction　of　-37.90%.　However,　incineration　and　biochemical　treatments　may　offer　environmental　benefits.