Microplastics (MPs) are plastic particles ranging from 0.1 to 5000 μm in size, which have gained significant attention due to their potential environmental and health impacts. MPs contribute to various harmful effects, including lipid peroxidation, DNA damage, activation of mitogen-activated protein kinase pathways, cell membrane damage, mitochondrial dysfunction, lysosomal defects, inflammation, and apoptosis. They pose a significant threat due to their widespread occurrence in food. Recent studies have indicated that MPs can cause oxidative stress (OS), a known factor in accelerating aging and various diseases. This review aims to critically evaluate whether the harmfulness of MPs is due to OS through a comprehensive analysis of recent research and existing scientific literature, as well as an assessment of the characteristics of MPs causing OS. The article also covers the analytical methodologies used in this field, highlighting the need for further research into the effects of MPs on OS. The findings suggest that MPs can lead to the formation of reactive oxygen species (ROS) through extracellular and intracellular processes, and their toxicity is size-dependent. MPs can alter the action of antioxidants, leading to increased ROS levels and OS. The review discusses the mechanisms of ROS generation, defense mechanisms against ROS overproduction, and the consequences of MPs-induced OS on cells, tissues, and organs. It emphasizes the importance of interdisciplinary research and mitigation strategies to address the environmental and health risks posed by MPs.Microplastics (MPs) are plastic particles ranging from 0.1 to 5000 μm in size, which have gained significant attention due to their potential environmental and health impacts. MPs contribute to various harmful effects, including lipid peroxidation, DNA damage, activation of mitogen-activated protein kinase pathways, cell membrane damage, mitochondrial dysfunction, lysosomal defects, inflammation, and apoptosis. They pose a significant threat due to their widespread occurrence in food. Recent studies have indicated that MPs can cause oxidative stress (OS), a known factor in accelerating aging and various diseases. This review aims to critically evaluate whether the harmfulness of MPs is due to OS through a comprehensive analysis of recent research and existing scientific literature, as well as an assessment of the characteristics of MPs causing OS. The article also covers the analytical methodologies used in this field, highlighting the need for further research into the effects of MPs on OS. The findings suggest that MPs can lead to the formation of reactive oxygen species (ROS) through extracellular and intracellular processes, and their toxicity is size-dependent. MPs can alter the action of antioxidants, leading to increased ROS levels and OS. The review discusses the mechanisms of ROS generation, defense mechanisms against ROS overproduction, and the consequences of MPs-induced OS on cells, tissues, and organs. It emphasizes the importance of interdisciplinary research and mitigation strategies to address the environmental and health risks posed by MPs.