<p>Plastic products are extensively used in packaging, construction, and a wide range of other sectors due to their lightweight, durability, and versatility. However, their resistance to degradation throughout the traditional life cycle—from production and consumption to disposal—leads to long-term accumulation of plastic waste in the environment. Over time, this results in the formation of microplastics and nanoplastics, which can persist for centuries. These particles contain chemical additives and also have a strong ability to migrate, posing significant ecological and human health risks. Despite increasing awareness of these issues, the recovery and recycling rates of plastic waste remain insufficient in many regions. This highlights the urgent need for effective analytical tools such as material flow analysis (MFA), which enables systematic quantification and tracking of plastic flows, stocks, and emissions across various stages of the life cycle. MFA offers valuable insights into the environmental fate of plastics and supports evidence-based policymaking for improved plastic management. With a growing number of international research applying MFA to plastics, it is essential for countries that have not yet engaged in such studies to understand the methodological framework, data demands, and policy relevance of this approach. This review provides a comprehensive synthesis of MFA applications at the national, regional, product, and material levels. It identifies current trends, methodological characteristics, and key findings in the field. Finally, future research directions are proposed to further enhance the role of MFA in addressing global plastic pollution challenges.</p>