In this study, ESO was mixed with EC to obtain green films with preferable performances. In this film both of the compositions were environment-friendly and bio-based. Conventional plasticizers (DBP and TEC) were also blended into EC solution to obtain DBP–EC and TEC–EC films as controls. A wide range of film properties, such as surface morphology, mechanical strength, thermal properties and permeabilities were determined for comparative study. Results showed that ESO was an efficient plasticizer and had potential to manufacture high-performance EC films for commercial use.