This work presents a methodology for the preparation of the surface prior to nanoindentation tests that increases the precision of the results due in rough surfaces. In applications where the maximum indentation size is dimensionally comparable with the specimen roughness, the accuracy and precision may be too poor. The developed methodology is directed to these cases. The methodology has been developed for thin coatings that are harder than the substrate. It has been validated and applied on TiO2 coatings deposited by PVD on Inconel® 718 and subjected to temperatures between 600 °C and 1100 °C, treatment that increases the specimen roughness. Modifying different parameters, it has been possible to analyse the improvement of the results due to the method and its uncertainty sources and to compare it with the usual nanoindentation technique. PALABRAS CLAVE/KEYWORDS: Nanoindentación, capas finas, rugosidad, abrasión superficial, PVD, óxido de titanio. Nanoindentation, thin coatings, roughness, surface abrasion, PVD, titanium oxide.