Microplastics (plastic particles < 5 mm) have received increasing attention in recent years due to their wide distribution in the environment. A bibliometric analysis was carried out using Web of Science, with significant contributions being observed by English and French research institutions in the microplastic field. Analysis of keywords revealed that the research hotspots were distribution, abundance, and risks of microplastics in the environment. Microplastics have been detected in water bodies and sediments of seven continents and four oceans. However, meaningful comparisons among studies are difficult due to the inconsistencies in sampling methods and concentration units. Moreover, studies have shown that the chemical composition of microplastics, as well as the pollutants adsorbed onto them, can have negative impacts on marine organisms. It remains unclear whether and how the consumption of aquatic products contaminated with microplastics affect human health. Therefore, it is advised that future research should focus on the transfer, accumulation, and effects of microplastics in the food chain.