This review aims to summarize the last advances on the field of protein engineering towards functional bionanomaterials. Albeit being this an emerging research field, multidisciplinary perspectives in the design of synthetic protein-based hybrid bionanomaterials have resulted in significant progresses. The review covers the definition of bionanomaterials as such and the description of the main methodological approaches currently employed for their assembly. In this context, special emphasis is placed on the fundamental role of protein design. Then, a general overview of the most recent advances related to the fabrication and application of protein-based bionanomaterials in several applications is provided, with special focus on catalysis. Finally, key aspects to be considered by the research community to establish the path for significant future developments in this promising field are discussed.