Micro-plastics have received widespread attention as a new type of refractory pollutants, which are mainly distributed in the ocean, coast, fresh water, soil and wetland systems,posing a potentially huge threat to the ecological environment. Wetlands are an important part of the ecological environment and play an important role in maintaining biodiversity. Therefore, microplastics pose a serious threat to wetland species diversity. This article systematically reviews the distribution characteristics and existing forms of microplastics in wetland systems, analyzes the toxicological effects of microplastics on animals, plants and microorganisms in wetland systems, summarizes the detection and analysis methods of microplastics in wetland systems and the focus of future research on microplastics is prospected.