Gliadins, the major component of wheat gluten, are considered an interesting candidate for preparing sustainable and biodegradable materials for food packaging applications. However, the development of gliadin-based films has not been totally explored and is limited to the formation of films obtained by the solvent-casting technique. In this work, a thermoplastic resin of gliadins (GLI) has been developed and blended with poly(ε-caprolactone) (PCL) in a co-rotating twin-screw extruder obtaining blend films with a PCL/GLI weight ratio of 1:1 and 1:0.3. The successful physical blending of both components was confirmed by FT-IR analysis. The tensile test was used to measure the mechanical performance of the developed films. This test showed that the incorporation of plasticized gliadins reduced the elastic modulus of the films, while the high flexibility characteristic of PCL was maintained. On the other hand, a considerable reduction in the oxygen permeability values under dry conditions was observed as the content of thermoplastic gliadins augmented in the films. Finally, the disintegration of the three film-formulations was assessed under home-composting conditions and the results after 180 days indicated that the presence of gliadins can accelerate the disintegration process of PCL.