With　different　proportions　of　nitrogen-argon　hybrid　shielding　gas,　the　experiment　of　CO2　laser　welding　of　2　mm　thick　SUS301L　austenite　stainless　steel　is　conducted.　The　microstructure,　comprehensive　mechanical,　and　surface　corrosion-resistance　properties　under　different　proportions　of　nitrogen　shielding　gases　are　investigated.　Experimental　results　indicated　that,　under　different　proportions　of　nitrogen　shielding　gases,　the　micro-morphologies　of　weld　joints　have　no　obvious　difference,　the　nitrogen　contents　are　the　same　as　that　of　steel　substrate,　and　the　phase　components　are　all　γ-austenite　with　combination　of　a　small　amount　of　δ-ferrite;　the　tensile　strength,　bend　strength,　and　micro-hardness　of　weld　joints　are　comparable　with　that　of　steel　substrate;　the　weld　joint　under　the　shielding　of　Ar　gas　possesses　the　best　corrosion　resistance　property;　with　the　increment　of　nitrogen　content　in　shielding　gas,　corrosion　resistance　of　weld　joint　surface　gradually　decreases,　but　the　corrosion　rate　shows　a　lowering　trend.　©　2016,　Chinese　Lasers　Press.　All　right　reserved.