The　erosion-corrosion　properties　and　interface　microstructure　of　a　Fe-B　alloy　that　contains　3.5　wt%　B　in　flowing　liquid　zinc　have　been　investigated　by　electron　backscattered　diffraction,　x-ray　diffraction,　and　scanning　electron　microscopy　to　clarify　the　flowing　effect　of　liquid　zinc　on　erosion　performance　using　a　rotating-disk　technique.　The　Fe-B　alloy　erodes　at　a　low　and　steady　rate　in　flowing　liquid　zinc.　Flowing　liquid　zinc　can　accelerate　the　iron　and　zinc　mass　transfer　to　form　Fe-Zn　compounds　and　promote　the　removal　of　loose　FeZn13.　Much　residual　corrosion-resistant　Fe2B　and　some　erosion　products　coexist　at　the　erosion　interface　because　of　the　chemical　and　micromechanical　effects　that　are　created　by　flowing　liquid　zinc.　The　failure　of　the　Fe2B　corrosion-resistant　skeleton　in　flowing　liquid　zinc　occurs　because　of　the　loss　of　supporting　matrix　and　also　the　formation　and　spread　of　microcracks　during　erosion.