The　droplet　transfer　and　arc　stability　of　three　kinds　of　self-shielded　flux-cored　wires　in　all-position　welding　applied　in　X70　pipeline　steel　were　tested　by　using　high-speed　video　camera　and　Hanover　Analysator.　The　results　showed　that　as　for　all-position　welding　arc　stability,　No.　1　wire　was　the　best,　No.3　wire　the　medium,　and　No.2　wire　the　worst;　coefficient　of　current　variability　could　reflect　welding　stability　more　accurately　than　standard　deviation;　average　short-circuiting　time　could　not　be　taken　as　the　only　way　to　judge　welding　arc　stability,　which　should　be　judged　by　combining　with　class　frequency　distributions　diagram　of　short-circuiting　time.　During　short　circuiting　transfer,　probability　density　distributions　diagram　of　arc　voltage　was　in　double-hump　shape,　and　probability　density　distributions　of　double-hump　shape　curve　and　convergence　of　the　whole　curve　could　be　regarded　as　important　references　for　evaluating　welding　arc　stability.