Whey protein and inulin were used to improve the compatibility between carvacrol ( Car ) and polyvinyl alcohol ( PVA ). PVA / Car antibacterial composite membranes were prepared by solvent casting method. The structure, morphology and thermal stability of the composite film were characterized by FTIR, SEM and TG, and its optical, mechanical, antioxidant, antibacterial and preservation properties were tested. The results show that the addition of Car endows the film with excellent antibacterial activity and oxidation resistance, but weakens the mechanical properties and optical transparency of the composite film. When the addition amount of carvacrol was 2 wt %, the elongation at break of the film was 82.2 %, the tensile strength was 34.85 MPa, the visible light transmittance was 67.9 %, and the free radical scavenging rate was 61.5 %. In the preservation experiment, compared with the blank group, the peak value of weight loss rate of blueberry in PVA / Car-2 group decreased by 32.2 %, the peak value of spoilage rate decreased by 40.0 %, the peak value of polygalacturonase activity decreased by 27.3 %, and the peak value of pectin lyase activity decreased by 10.2 nmol / min / g, which could delay the spoilage of blueberry and maintain the commercial value of blueberry.