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ZrW₂O₈ powders were prepared by sol-gel method with PVP as the additive. The effect of PVP on the morphology was studied and negative thermal expansion property of ZrW₂O₈ powders was also investigated. The precursor of ZrW₂O₈ was analysized by thermogravimetric and differential scanning calorimetry (TG-DSC). The structure and morphology of the resulting powder were characterized by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM) respectively. The results show that the resulting powder is single cubic α-ZrW₂O₈ phase. The addition of PVP can effectively change the morphology of the powder, with the increasing amount of PVP, morphology of the particles changes from irregular aggregates to rod-like, fan-shaped and short rod particles. The results of <i>in-situ</i> X-ray diffraction measurement indicate that ZrW₂O₈ powder prepared with the addition of PVP has good negative thermal expansion property.