Low density, highly porous and hydrophobic cellulose-based new material, Xerocellulose, was prepared and characterised. First, tritylcellulose with different degrees of substitution (DS) was synthesised in homogeneous conditions. Xerocellulose was then prepared from tritylcellulose via dissolution–coagulation–drying route, similar to other polysaccharide-based aerogels, but drying was performed in ambient room conditions. The new material has a density between 0.1 and 0.2 g/cm3 and is highly hydrophobic with contact angle 140° for DS = 0.72. Compared with cellulose aerogel and pristine microcrystalline cellulose, Xerocellulose obtained from tritylcellulose with DS = 0.72 showed a drastically decreased water vapour uptake. The evolution of Xerocellulose density and morphology as a function of the DS is presented and discussed.