Microplastics pose a significant environmental threat as they can be consumed directly or indirectly by various marine organisms. This investigation explores the ecological hazards of microplastic pollution in marine life, with an emphasis on fish in Banten Bay, Indonesia. The sampling spots were in Banten Bay where traditional fishing gears known as “bubu” were used and nets. This study represents an inaugural examination of microplastic contamination in selected fish species including Gambusia affinis, Stolephorus indicus, Scatophagus argus, Epinephelus coioides, Rastrelliger sp., Parapenaeopsis sculptilis, and Leiognathus sp. As a result, microplastics were detected in each fish, with a notable increase in concentrations within the gills (7.85 ± 3.54 items/ind) as opposed to the digestive tract (4.95 ± 2.15 items/ind). Their presence indicated a significant difference (p < 0.01), primarily observed as fragments and filaments. Nine distinct polymer types were identified with FT-IR in fish samples collected from Banten Bay, including polyethylene terephthalate, polyvinyl chloride, polyester, polyurethane, ethylene propylene, polypropylene, polyethylene, polystyrene and polyphenylene sulfide. Microplastics were primarily detected within the size range of 20 to 4510 µm. Microplastic contamination in fish causes detrimental implications on aquatic ecosystems and human health, since the particles exist in the food chain, altering the biological activities of fish, and potentially posing hazards to consumers. Considering the closeness of Banten Bay to Indonesia's capital and economic hub, immediate preventive actions are essential to safeguard human health and the ecosystem. Additional investigation into plastic degradation and waste management is crucial for comprehending the origins of contamination. The results establish a foundation for continuous monitoring of microplastic risks in Banten Bay and other swiftly evolving coastal ecosystems in Northeast Asia.