Corn starch-based nanocomposite films usually have low moisture barrier properties. The addition of virgin coconut oil (VCO) as a hydrophobic component can improve the nanocomposite film's characteristics, especially the film's permeability and elongation properties. This study aimed to determine the role of VCO with various concentrations (0,3,5 wt%) on the physical, mechanical, and water vapor transmission characteristics of corn starch/NCC-based nanocomposite films. The results showed that the concentration of 3 wt% VCO was most effective in reducing the WVTR value of nanocomposite films with a value of 4.721 g/m2.h. While the value of tensile strength was 4.243 MPa, elongation 68.58%, modulus of elasticity 0.062 MPa, thickness 0.219 mm, lightness 98.77, and water solubility 40.51%. However, the addition of 5 wt% VCO was more effective in increasing the elongation properties of the film. The addition of VCO gave the appearance of a porous film surface and a finer structure was formed. The FTIR test on corn starch nanocomposite films with the addition of VCO did not show any new absorption peaks. The results of this study may provide opportunities for the development of nanocomposite films as biodegradable packaging in the future.