The　effects　of　different　shielding　gases　CO2,　Ar　and　mixture　gases　(CO2+Ar)　on　the　slag　detachability　of　type　347L　flux-cored　wire　for　stainless　steels　containing　Nb　were　investigated.　Slag　detachability　of　home-made　GDQA347L　(3　#)　was　compared　with　that　of　TFW-347L　flux-cored　wire　and　AT-Y347L　flux-cored　in　the　same　condition.　The　effects　of　slag　microstructure　and　macroscop　on　the　slag　detachability　of　three　type　flux-cored　wires　were　investigated.　The　results　showed　that　the　best　slag　detachability　of　GDQA347L　flux-cored　wire　was　under　the　shielding　gas　of　Ar,　and　the　better　slag　detachability　was　under　the　shielding　gas　of　mixture　gas　(CO2+Ar),　and　the　worst　slag　detachability　was　under　the　shielding　gas　of　CO2.　Because　the　CO2　gas　transfer　into　active　gas　at　high　temperature　with　strong　oxidizability　which　will　make　detachment　difficult　on　the　slag　detachability,　and　it　is　proved　that　the　regular　of　microstructure　of　three　flux-cored　wires　under　different　shielding　gases　is　similar.　It　is　benefit　for　the　slag　detachability　when　the　trunk　of　the　strip-shaped　slag　microstructure　is　long　and　the　area　of　the　branch　is　large.