Polyvinyl chloride (PVC) is a general-purpose plastic with excellent comprehensive properties, and it is also the second largest resin variety after polyethylene. As one of the most commonly used plastics, PVC is used in many fields, but there are still some defects such as poor toughness, poor heat resistance, and so on. Therefore, the modification of PVC materials is the main research direction in the field of materials. This paper introduces two modification approaches in the modification of PVC, chemical modification and physical modification. Chemical modification includes graft modification and cross-linking modification, and cross-linking modification can be divided into radiation cross-linking and chemical cross-linking. Physical modification includes elastomer modification. In the study of modification methods introduced in this paper, grafting modification can improve the plasticity of the material, and can also give the material special properties such as antibacterial properties. Crosslinking modification can improve the strength of materials, such as tensile strength and compressive strength. Physical modification can improve the impact strength of materials. This paper provides an overview of PVC modification and insight into improvements in common polymeric materials.