The fabrication of novel systems where enzymatic and metallic actives sites can be directly interacting represent a very fancy strategy for sustainable processes. One of the new strategies goes to the direct formation of metal nanoparticles in situ on a protein network as scaffold. This biological entity is the key element because conserved its biological catalytic efficiency but induced the final metallic nanoparticles generation on their structure. This method allows to obtain bifunctional enzyme‐metallic catalysts with excellent versatility and efficiency in a different kind of reaction and experimental conditions. In this concept article, the relevant aspect in term of the fabrication of this enzyme‐metal nanoparticles hybrids and specific recent reported examples where they have been successfully applied in significant cascade processes will be described.