Herein, carboxymethyl cellulose nanocomposite films incorporated with graphene oxide and reduced graphene oxide were successfully prepared by a novel approach for the first time, and their alternative properties compared with the original carboxymethyl cellulose films were disclosed. For carboxymethyl cellulose/reduced graphene oxide film preparation, sodium borohydride was used as a chemical reducing agent. The carboxymethyl cellulose films were prepared by using a solvent casting method, followed by an acid treatment to decrease the water solubility (98%) while enhancing the tensile strength (15%) and elastic modulus (32%) of the original carboxymethyl cellulose films. Overall, the addition of 1.0 wt% graphene oxide and reduced graphene oxide to the treated films increased the water solubility, water absorption, tensile properties and electrical conductivity. Particularly, the electrical conductivity was predominantly enhanced 1.3×105 times with graphene oxide and 2.2×105 times with reduced graphene oxide compared to the treated carboxymethyl cellulose film. The electrical conductivity of the treated carboxymethyl cellulose film also increased with an increase in reduced graphene oxide. The effects of reduced graphene oxide on the water solubility, water absorption, tensile properties and electrical conductivity of the treated carboxymethyl cellulose film were more pronounced than those of graphene oxide, especially for the electrical conductivity. In conclusion, graphene oxide and reduced graphene oxide might be alternative nanofillers for improving the carboxymethyl cellulose film properties. For the future applications, carboxymethyl cellulose/reduced graphene oxide films prepared by using this approach might be employed as alternative materials in electronic packagings and electrochemical biosensors.