Microplastic pollution is a serious global issue affecting freshwater systems, coastal regions, and oceans. These non-biodegradable materials have a detrimental impact on marine species and ecosystems, causing disruption to their feeding, breathing, and reproduction. In this study, 120 samples of two species of shrimp, P. monodon and P. indicus, from ten locations in the Negombo lagoon in Sri Lanka were analyzed. A total of 415 items were identified as microplastic with an average of 8.29 ± 4.63 items per gram in P. monodon and 5.52 ± 3.78 items per gram in P. indicus. The majority of microplastics identified were fibers (93%), and the remaining being fragments. Most of the microplastics were >1000 μm, and the most prevalent color was blue (61%), followed by red (15%), black (9%), and others. These comprised of polystyrene, polyamide, polyester, polypropylene, and rayon, as identified by FTIR spectroscopy. This study highlights the prevalence of microplastics in shrimps harvested from the Negombo lagoon and the potential impact on marine life.