Chitinous scaffolds isolated from the skeleton of marine sponge Aplysina cauliformis were used as a template for the deposition of polyhedral oligomeric silsesquioxanes (POSS). These chitin–POSS based composites with hydrophobic properties were prepared for the first time using solvothermal synthesis (pH 3, temp 80°C), and were thoroughly characterized. The resulting material was studied using scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and thermogravimetry. A mechanism for the chitin-POSS interaction after exposure to these solvothermal conditions is proposed and discussed.