The present study describes the physical, antioxidant, and antimicrobial properties of biodegradablefilms prepared by incorporating different concentrations (1, 2, and 3% v/v) of Zataria multiflora Boiss(avishan-e shirazi) essential oil (ZEO) into carboxymethyl cellulose (CMC) film. The films’ tensile strength,elongation at break, water-vapor permeability, optical characteristics, microstructure, and antimicrobialand antioxidant properties were investigated. The results indicated that the film containing 1% ZEO hadthe highest tensile strength and elongation at break. The control film showed the lowest water-vaporpermeability. The resulting optical data showed that the control films were transparent in appearance;transparency was significantly reduced by an increase in ZEO concentration. Solubility in water decreasedwith increased ZEO. Films with ZEO, especially at higher concentrations, were more effective againstall tested bacteria than the control film. Those films incorporating essential oil revealed antioxidantproperties as well; this effect was greatly improved when the proportion of ZEO was increased. Theresults indicated that the antioxidant and antibacterial activity of ZEO is retained when it is used in CMCfilm. These properties with some good physical characteristics suggest applications for ZEO-incorporatedfilm in a wide range of food products.