Millions of tonnes of plastic are created annually, and in the aquatic environment, microplastics are a new pollutant that has steadily gained awareness in the Asian region. Although much more research on microplastics in freshwater has been published in recent years, there are still questions about the potential sources and routes of microplastics into freshwater ecosystems. Thirty-three publications on the sources and transport of microplastics in freshwater ecosystems were evaluated using a systematic quantitative literature review approach. We assessed the findings relating to the shape and colour of microplastics reported in water and sediments. This review found that microplastics are frequently detected in various freshwater bodies in six regions, including rivers, estuaries, lakes, and wetlands. The results of this review indicated that research on microplastics in Asia has gained attention since 2016, with a gradual increase in the number of studies from 2019 onwards. The results showed that more than half of the studies focused on China. It was discovered that microplastics infiltrate freshwater ecosystems either from direct or indirect sources. The typical shapes of microplastics identified are fibre, fragment, film, foam, pellet, and sheet. The most common colours of microplastics found in freshwater are transparent, blue, red, white, and black. Fishing tools, textiles and clothing, beauty products, vehicles, and product packaging are examples of direct sources, while some indirect sources are aquacultural, agricultural, domestic sewage, and tourism. Microplastics can be transported to water bodies by surface runoff, fragmentation of larger-size plastics, and erosion of the surrounding land. Moreover, this study revealed that only a few studies discussed the transportation of microplastics in sediments compared to water. This implies the need for further research on the transportation of microplastics in sediments to holistically address this new water pollutant.