Metal　transfer　of　self-shielded　flux　cored　for　vertical　down　welding　condition　is　studied　by　using　high　speed　photographic　method.　The　results　show　that　the　modes　of　metal　transfer　are　short　circuit　transfer,　bridging　transfer　without　arc　interruption,　explosive　transfer,　and　globular　transfer.　Bridging　transfer　without　arc　interruption　is　the　main　mode　and　it　also　contains　two　kinds　of　modes:　explosive　transfer　and　surface　tension　transfer.　The　characteristic　of　the　former　is　the　explosion　of　the　bridge　and　the　later　is　that　the　molten　droplet,　contacting　with　molten　pool,　transferring　into　the　pool　by　the　action　of　surface　tension.　As　the　welding　current　grows,　the　droplet　becomes　small,　the　frequencies　of　metal　transfer　increases,　the　amount　of　bridging　transfer　without　arc　interruption　and　explosive　transfer　increases,　and　the　amount　of　short　circuit　transfer　decreases.