Abstract: In recent years, multifunctional nanocomposite films based on natural biopolymers, including protein and polysaccharides, have attracted great attention in emerging fields such as biomedicine, food packaging, and flexible electronics. In this review, the effect of nanomaterials with various structures and functions was summarized on the physicochemical performance and multifunctionality of the resultant biopolymer-based nanocomposite films, and their application potentials were also discussed in the biomedicine, food packaging, and flexible electronics fields. Research trends of the nanocomposite films were finally prospected. This review can provide significant reference for the development and application of novel multifunctional biopolymer-based nanocomposite films.