Basalt fiber, a type of high-performance fiber, is produced by drawing from basalt or rocks of similar compositions after high-temperature melting. The homogeneity of the melt during fiber preparation critically determines fiber quality, yet the dynamic phase transition process during basalt melting remains poorly understood. This study investigated the melting behavior of Hainan Island basalt for fiber production through high-temperature melting experiments, combined with X-ray diffraction (XRD), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC) analyses. The results showed that under an air atmosphere, the sample lost adsorbed water from room temperature to 113℃, smectite melted at 804~849℃, pseudobrookite, clinopyroxene and plagioclase with low-An melted in large quantities at 1 075~1 193℃, and high-An plagioclase and hematite melted at 1 220~1 297℃. The various mineral components melted in order of melting point from low to high, but during the melting process, oxidation reactions occurred to produce hematite and pseudobrookite, causing the complete melting temperature of basalt to increase by about 120℃. The grain size of hematite increased significantly with increasing temperature, which was attributed to crystal regrowth at high temperatures. This study provides a theoretical basis for optimizing the melting process of basalt for fibers.