The　Belt　and　Road　Initiative　(BRI)　is　an　open　platform　for　international　cooperation　proposed　by　China　to　promote　common　global　development　and　prosperity.　The　BRI　can　promote　the　optimal　allocation　of　resources　and　promote　in-depth　cooperation　in　international　trade.　Meanwhile,　it　can　establish　a　green　supply　chain　cooperation　network　to　help　BRI　countries　achieve　green　transformation.　BRI　has　made　a　notable　contribution　to　the　rapid　growth　of　cross　-border　trade.　However,　it　has　also　brought　environmental　impacts.　Given　that　little　attention　has　been　paid　to　the　trade　-embodied　particulate　matter　2.5　related　human　health　impacts　(PM2.5-HHI)　throughout　the　BRI,　this　study　accounts　for　and　traces　the　embodied　PM2.5-HHI　flows　between　the　BRI　countries　and　non　-Belt　and　Road　Initiative　(non-BRI)　countries.　Moreover,　this　study　also　uncovers　the　critical　socioeconomic　drivers　of　PM2.5-HHI　changes　in　BRI　countries　during　1990-2015,　based　on　the　multi　-regional　inputoutput　based　structural　decomposition　analysis　(MRIO-SDA).　Results　show　that,　firstly,　BRI　countries　had　significantly　increased　their　economic　added　value　by　exporting　products　to　the　non-BRI　countries.　They　also　have　brought　PM2.5-HHI　to　themselves.　Secondly,　the　final　demand　of　BRI　countries　was　the　largest　potential　driving　force　of　PM2.5-HHI　of　BRI　countries.　Thirdly,　the　emission　intensity　change　of　BRI　is　the　key　socioeconomic　factor　for　reducing　PM2.5-HHI.　While　per　capita　final　demand　level　change　of　BRI　and　production　structure　change　of　non-BRI　are　the　key　socioeconomic　factors　for　increasing　PM2.5-HHI.　The　study＇s　findings　on　the　one　hand　can　help　reduce　the　PM2.5-HHI　and　impacts　of　environmental　pollution　of　BRI　countries　from　a　global　perspective　by　providing　scientific　support.　On　the　other　hand,　they　can　help　provide　relevant　policy　recommendations　for　the　green　transformation　of　BRI　and　the　construction　of　green　BRI.