Polyphenols are a class of bioactive compounds of natural origin, which are gaining great attention in biomedical applications for their antioxidant, anti-inflammation, and anticancer, properties, as well as for their positive impact on bone health. Therefore, they can be used to functionalize biomaterials, endowing them with multifunctional properties. In this study, green tea polyphenols (TPH) and tannic acid (TA) have been used to functionalize two kinds of biomaterials: porous titanium disk and chitosan hydrogels. Porous titanium offers mechanical strength with low rigidity, minimizing the stress-shielding phenomenon, while its optimized porosity increases the capacity of osseointegration. On the other hand, chitosan is a biocompatible and biodegradable polymer of natural origin, widely used for its ability to form hydrogels with tunable properties.