Abstract, Μarine pollution due to plastic waste is a globally recognized threat that needs effective actions of control and mitigation. Continental plastic litter is flushed into the oceans by storms andriver systems or is directly discharged into coastal waters. At a global scale, 60% of plastic waste floating in the oceans is discharged from coastal areas in all continents. Plastic waste is degraded sowly into fragments of smaller size and microplastic (MPs) pollution now appears as one of the world’s environmental main concerns. Scientists change their analytical and detection techniques and numerous monitoring studies were promulgated in the last decade to determine the levels of microplastic pollution at sea and in oceans. The small size of microplastics and nanoplastics makes them potentially bioavailable, via ingestion, to a wide range of marine organisms as they overlap with the size range of their prey. Ingestion of microplastics and nanoplastics have been reported in many in the organs and tissues of most marine species over a broad range of taxa. Biomonitoring of plastic pollution (micro- and nano – size) in marine species should be considered as an additional tool to assess the state of the marine environment. Using marine organisms for biomonitoring of plastic pollution can provide crucial information for the abundance of plastic debris, distribution, type of plastic, and toxic characteristics for adverse effects on specific tissues of marine species. Numerous analytical toxicological studies in bivalves (including oysters, mussels, and clams) have been proved to be suitable bioindicators to identify contamination levels, abundance and types and characteristics of microplastics and nanoplastics.Nanoplastics (sizes in the range from 1 to 100 nm) with similar mechanisms can affect the metabolism, fertility, and mortality of marine organisms. However, there is no significant difference between nanoplastics and microplastics with regard to the adverse health and oxidative effects. Recent studies indicated that nano- and micro- sized plastics and plastic waste in general caused various adverse effects on the growth, development, behaviour, reproduction, and oxidative stress and DNA damage leading to increased mortality of aquatic animals. This review collected a series of scientific papers, reviews and scientific reports concerning the use of marine species for biomonitoring and as potential biondicators of marine pollution by plastic waste.