Vegetable oil-based plasticizers are regarded as the most promising bio-based environmental plasticizers owing to the their wide source of raw materials, adjustable structure, excellent plasticity, non-toxicity and biodegradability. However, the high proportion of long chain alkyl in the structure of vegetable oil-based plasticizer results in poor compatibility with PVC resin, which is typically used as an auxiliary plasticizer, and the application value has not been fully incarnated. In recent years, domestic and foreign scholars have chemically modified the vegetable oil-based plasticizer structure and developed a series of multifunctional vegetable oil-based plasticizers (such as solubilizationt, heat tolerance, flame retardant, suppressed migration, etc.) to achieve the "improvement of quality and efficiency" of vegetable oil-based plasticizer. In this paper, beginning with the molecular structure design of vegetable oil, the existing literature was compiled, analyzed and summarized through the combination of molecular simulation, micro and macro analysis methods, and the "structure-activity" relationship between the structure of plasticizer and the performance of plasticized PVC products was established, aiming to provide a theoretical basis for the structural design and industrial production of high-performance and multi-functional vegetable oil-based plasticizer.