Veracruz is a megadiverse state facing great water resource management challenges. The contamination of water bodies with external materials of anthropogenic origin stands out, including those derived from plastic products, which are deemed ubiquitous, emerging contaminants that have gained notoriety in recent decades due to the extent and effects of their presence, persistence and distribution in aquatic ecosystems. Being a significant environmental threat, their presence, persistence and distribution in aquatic ecosystems are deserving of a more detailed study. This research focused on analyzing microplastic (MP) retention and characterization in environmental matrixes (water and sediment) in the Bobos River’s lower basin, also taking into account other water physicochemical parameters, including a pH range from slightly acidic (5.17) to slightly alkaline (8.94) as the maximum value and an average temperature of 28.87 °C (83.96 °F). MPs are most frequently found in the form of blue-colored fibers. A polymer analysis by Fourier Transform Infrared Spectroscopy (FTIR) revealed that the most common polymer was polyethylene (PE), which is the main component of most agricultural mulch and agrochemical containers. This research aims to enhance the understanding of the plastic matter contamination of water bodies, pointing out the need for further and deeper research on this subject.