Abstract: As a new type of pollutant, microplastics exist widely in soil and can combine with heavy metals such as cadmium to form compound pollution, which poses a serious threat to farmland soil ecosystem. Based on the current situation of combined pollution of microplastics and cadmium, the research progress in microplastics and cadmium pollution sources and migration characteristics, the interaction between microplastics and cadmium and their ecological effects in farmland soil were reviewed, and the research prospects were put forward. The study of combined pollution of microplastics and cadmium has gradually become a research hotspot in the field of environmental science since 2016. Microplastics were detected in farmland soil in all provinces, municipalities, autonomous regions of China, and their sources mainly included agricultural plastic film, organic fertilizer, coated fertilizer, sludge, surface runoff and agricultural irrigation, atmospheric sedimentation and tire wear particles. The content of microplastics in soil of mulched planting area is higher in China. The combined pollution of microplastics and cadmium has a series of effects on soil physical and chemical properties, plant and animal growth and microbial activities, and may eventually enter the human body through the food chain, resulting in potential health risks. In the future, research can be carried out from the aspects of the formulation of soil microplastics sampling and detection norms, the interaction mechanism between microplastics and cadmium, research and development of composite pollution remediation technologies, and policy formulation, so as to provide references for the risk control and treatment of soil microplastics and cadmium composite pollution.