DensityofmoltenNiandNi-Walloyswasmeasuredinthetemperaturerangeof1773~1873Kwithasessiledropmethod.ThedensityofmoltenNiandNi-Walloystrendstodecreasewithincreasingtemperature.ThedensityandmolarvolumeofthealloystrendtoincreasewithincreasingWconcentrationinthealloys.ThecalculationresultshowsanidealmixingofNi-Walloys.