In this work, we report the preparation of ultrathin submicro- and nanoporous cellulose films onto Si (100). The effect of different experimental conditions of preparation on the film surface morphology was studied, namely the role of the film casting method (spin- versus dip-coating), solvent (toluene or tetrahydrofuran), substrate pretreatment (hydrophilicity degree), and regeneration procedure with HCl vapors (two consecutive dips followed by regeneration or regeneration after each dip). The surface morphological structures presented in this work were never obtained before without the use of templates. A rather regular two-dimensional pore network was obtained onto the less hydrophilic Si substrate (contact angle≅68°), after two consecutive dips (with an intercalary rotation of 180º) in trimethylsilyl cellulose diluted in toluene and regeneration at the end. All the surfaces were characterized by atomic force microscopy.