Abstract: The primary short circuit melted mark and secondary short circuit melted mark of H62 brass conductor were prepared by fire simulation tests, and the solidification structure of different melted marks was studied. The results show that the primary short circuit melted mark had obvious characteristics of transition zone. The solidification structure at room temperature of bead-shaped primary short circuit melted mark was α phase with dendritic morphology, and the mass fraction of Zn element was lower than 32.5%. The solidification structure at room temperature of dimpled primary short circuit melted mark was α+β phases; the α phase was precipitated into β phase grains in acicular shape along the grain boundaries of β phase, and the acicular crystal of α phase did not penetrate the grain boundaries of the β phase; the mass fraction of Zn element was higher than 32.5%. The secondary short circuit melted mark had a bead shape with obvious characteristics of transition zone; the solidified structure at room temperature was α+β phases, and the α phase was feather-like and arranged with direction; the mass fraction of Zn element was higher than 32.5%.