Mikroplastik adalah partikel plastik yang berukuran ≤ 5 μm dan tidak dapat larut dalam air. penelitian ini bertujuan untuk mengetahui keberadaan, karakteristik, kelimpahan yang terakumulasi diperairan. metode pengambilan sampel ikan bandeng dilakukan dengan mengambil ikan bandeng sebanyak 7 ekor pada masing-masing di lokasi tambak, selanjutnya dibawa ke laboratorium untuk dilakukan ekstraksi kemudian diuji laboratorium. hasil penelitian ditemukannya keberadaan mikroplastik pada semua lokasi penelitian dengan karakteristik secara fisik pada mikroplastik diklasifikasikan berdasarkan warna, jenis, dan ukuran. ada 6 jenis warna yang ditemukan antara lain, hitam, biru, merah, transparan, coklat, kuning. warna yang paling dominan yaitu pada warna hitam dengan presentase 44% dan warna paling sedikit yaitu warna kuning dengan presentase 1%. adapun empat jenis mikroplastik yang ditemukan yaitu fragmen, fiber, film, pelet dengan jenis mikroplastik yang paling dominan yaitu fiber dengan presentase 43% diikuti dengan fragmen dengan presentase 30%, film dengan presentase 27% dan pelet dengan presentase paling sedikit yaitu 1%. ditemukan juga 9 ukuran mikroplastik yang cukup bervariasi dimana ukuran yang paling dominan terdapat pada ukuran 100-500 μm sebanyak 154 partikel dan ukuran paling sedikit yang ditemukan yaitu pada ukuran 2000-5000 μm sebanyak 4 partikel. kata kunci: kota tarakan, mikroplastik, perairan

Microplastics are plastic particles that are ≤ 5 μm in size and cannot dissolve in water. along with the increasing population and the number of community activities, this has led to an increase in the amount of plastic waste produced by humans directly and indirectly. the possibility of microplastic contamination in fish consumed by humans would certainly be very detrimental to humans. one prevalent consumption fish in tarakan is milkfish (chanos-chanos). generally, the milkfish consumed by the public comes from ponds, so it is necessary to identify milkfish samples in tarakan ponds. the research result found the presence of microplastics at all research locations, with the physical characteristics of the microplastics classified based on colour, type and size. six types of colours were found, including black, blue, red, transparent, brown and yellow. the most dominant colour was black, with a percentage of 44%, and the least dominant colour is yellow, with a percentage of 1%. the four types of microplastics found were fragments, fibre, film, pellets, with the most dominant type of of microplastics being fibre with a percentage of a 43%, followed by fragments with a percentage of 30%, film with a percentage of 27% and pellets with the minor percentage, namely 1%. there were also nine quite varied sizes of microplastics found, where the most dominant size was 100-500 μm with 154 particles, and the smallest size found was 2000-5000 μm with four particles. keywords: tarakan city, microplastics, waters