Abstract: Polyvinyl chloride (PVC) foam system was modified with the blending of recycled thermoplastic acrylic resin and paint slag, and the foam composite was prepared by using hot-pressing method. The effects of the paint slag dosage on the shear viscosity of blending systems and microstructure, apparent density, mechanical properties and heat resistance of the resulting PVC foam composites were investigated. The results indicated that the addition of acrylic resin paint slag could increase the interaction between PVC molecular chains, improve the shear viscosity and regulate the melt strength of PVC foaming systems, thus leading to PVC foams with small and homogeneous cellular structures. With adding of 10% paint slag, the shear viscosity of blending system increased from 2 726.1 Pa·s to 9 029.4 Pa·s, and the resulted PVC foam composite exhibited optimal comprehensive performances, in which the apparent density decreased from 0.63 g/cm ³ to 0.49 g/cm ³, the flexural and impact strength increased from 13.6 MPa and 4.7 kJ/m ² to 18.2 MPa and 8.9 kJ/m ², respectively, and T_g increased from 72 ℃ to 75 ℃.