Although soy protein plastics without any additive have a brittle behavior, which makes processing difficult, addition of plasticizers is an effective way to obtain flexible SPI-based films. Final properties of plasticized soy protein films prepared by casting were analyzed, and the effects of plasticizer content and processing conditions were studied and related to the differences in protein-plasticizer interactions. It is also worth to note that water was the solvent used to produce films, which is an important benefit from the economical and environmental point of view. Furthermore, designing biobased packaging films involves many considerations to successfully manufacture sustainable packaging, including environmental aspects, and Life Cycle Assessment (LCA) is a practical key tool to measure environmental impact from the extraction of raw materials to ultimate disposal