Malt bagasse (BM) is a byproduct of the brewing industry with low added value but is rich in fiber and proteins, making it a potential product to be incorporated into the formulation of biodegradable films. This work aimed to produce biodegradable films based on wheat flour and PBAT added with different concentrations of BM (0 – 7.5 %) by blown extrusion. The films were characterized by physical, optical, morphological, thermal properties, and compostability. It was possible to produce biodegradable films by blown extrusion with excellent processability. BM increased film opacity with a heterogeneous, rough, and yellowish surface. Also, BM addition in the films reduced their hydrophilicity; however, as the BM concentration increased, there was a reduction in the elongation at break, tensile strength, and thermal stability of the films. The film with 7.5 % BM showed greater fragmentation and mass loss during the composting process, possibly due to the fragile matrix that facilitated the action and degradation by microorganisms. The biodegradable films containing BM are viable alternative for packaging production for different products.