The objective of this work was to study the production of new biodegradable thin films. As a result of increasing problems with regard to the disposal of domestic waste, particularly plastics, a new class of polymers especially designed to be biodegradable has been undergoing development. However these biodegradable plastics still have a limitation, i.e. high cost. This research studied methods of lowering the cost of biodegradable plastic and of improving its properties by using epoxidized natural rubber as a another polymer for polymer blends. Thus, ternary blends of epoxidized natural rubber (ENR), poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) were studied and prepared using a twin-screw extruder, followed by use of a chill roll cast film extruder or a blown film extruder, to produce biodegradable film. The concentration of ENR in the ternary blends was fixed at 10 wt%, with the remainder being PLA and PBAT. In some proportions of the film blends, Irganox and Uvinul were introduced to increase the thermal stabilization and UV stabilization, respectively. The mechanical and thermal properties were evaluated, including the thickness, color, and water vapor permeability (WVP) of the biodegradable films.