In this work, the conditions for the preparation of stable nanometer zirconia slurries with high solids content for the production of aqueous-gel-tape-casting objects with improved properties are identified. Influences of the powder and dispersant on the theological properties were investigated. The result indicated the polyelectrolyte dispersant greatly affected the surface charge of nanometer tetragonal zirconia powder and the theological behavior of nanoparticles zirconia's suspensions. For each factor there exists an optimum range in which low viscosity was achieved for a slurry of high solid content. The proper content of the dispersant is between 0.8 and 1.2 wt.%. The theology character of high solid loading slurries is non-Newtonian flow-'shear-thinning' character as the shear rate is increased. The viscosity of the 77 wt.% powder loading slurry with about 1.0 wt.% polyelectrolyte (based on the powder) was 0.35 Pa s at the shear rate of 110 s(-1). The slurry at the optimum conditions met the demands of aqueous-gel-tape-casting process. (C) 2003 Elsevier Science B.V. All rights reserved.