In this paper, we introduce a parylene-coated cellulose nanofiber film. The parylene coating overcomes the limitations of cellulose nanofiber films used as food packaging films. The disadvantages of cellulose nanofiber films are that they are poor oxygen barriers and have low water resistances. This parylene-coated film achieved a low oxygen transfer rate (OTR) of <5 ml/m²/day because the parylene coating effectively covered the surface pores. In contrast to a pristine cellulose nanofiber film, the parylene-coated film was hydrophobic and exhibited a water contact angle of >75º. Similar to macro-cellulose papers, the pristine cellulose nanofiber film absorbed water and tore easily. The parylene-coated film was not permeable to water. However, the coating did not yield a significant improvement in the mechanical properties or light transmittance. We also investigated the change in surface morphology by the parylene coating. The parylene-coated film has great potential as a food packaging film owing to its improved oxygen barrier and water resistance characteristics.