Abstract: Ultra-low density cellulose triacetate (TAC) spheres and ellipsoid aerogels used for quasi-spherical Z-pinch were fabricated in special moulds by using TAC granules as raw material and controlling the processing of dissolution, gelation and supercritical carbon dioxide drying. The solution-gelation processing of TAC solution when cooled to room temperature, the rheological behavior of TAC gel, and the inside microstructure and the thermogravimetry (TG) analysis of TAC aerogel were investigated. TAC solution turns to gel with high transparence when cooled to room temperature. The SEM photos showed that the aerogels had a three-dimensional nanostructured solid network and a nanoporous network together with fiber sizes about 20-40 nm. The TAC granules and the TAC aerogels were thermally stable up to 320 ℃ as indicated by TG analysis. These TAC sphere and ellipsoid aerogels were successfully used in quasi-spherical Z-pinch experiment.