The behaviors of electrical resistivityvs temperature (ρ-T) of the molten p-type thermoelectric aloy Bi0.3Sb1.7Te3 (at.%) were explored in heating and cooling processes. An obvious hump appeared on theρ-T curve from 932℃ to 1,020℃ at the heating process, while the curve became smooth in the folowing cooling, which suggests an irreversible temperature-induced liquid-liquid structure transition (TI-LLST) occurred in the liquid aloy. Based on this judgment, solidiifcation experiments were carried out to ifnd out the effects of the different liquid states. It was veriifed that, for the melt experiencing the presumed TI-LLST, both the nucleation and growth undercooling degrees were elevated and the solidiifcation time was remarkably prolonged. On the other hand, the conifguration of Bi0.3Sb1.7Te3 phase was reifned, and its preferential orientation was weakened.