The use of cellulose, the most abundant renewable, biocompatible and biodegradable natural polymer, is nowadays reconsidered thanks to new non-toxic and powerful cellulose solvents which allow making materials with various functionalities. High value-added cellulose-based porous materials are thus very attractive for diverse applications, from bio-medical (controlled release, scaffolds) to engineering (thermal insulation) and electrochemical (when pyrolized). In this work, novel extremely porous and ultra-lightweight cellulose-based biomaterials are prepared via dissolution-coagulation route. Three drying ways were used: (i) supercritical CO2 drying (aerogel); (ii) freeze-drying (cryogel); (iii) vacuum-drying (xerogel), resulting in very different morphologies. Porous celluloses were characterised with bulk density and specific surface area via nitrogen adsorption; morphology was investigated by high-resolution SEM and pore sizes were estimated when possible. Finally, the mechanical properties were also studied in details under the uniaxial compression. The influence of drying method, cellulose molecular weight and concentration on the structure and properties of the final porous materials will be presented and discussed. Acknowledgements: The work is part of «Aerowood» project financed by WoodWisdom Net+ EC program. The authors thank Prof. B. Saake from Hamburg University (Germany) for providing and characterisation of the native celluloses.