Perairan Pantai Desa Lamu merupakan salah satu pantai potensial di Teluk Tomini karena memiliki keanekaragaman hayati penting. Aktifitas antropogenik disekitar perairan pantai berpotensi memberikan dampak pencemaran kualitas air. Penelitian ini bertujuan untuk menilai status pencemaran di Perairan Pesisir Desa Lamu Kabupaten Gorontalo menggunakan indeks trofik-saprobik berdasarkan keanekaragaman bivalvia. Penelitian dilakukan pada bulan Februari-Mei 2024. Penelitian ini menggunakan metode purposive random sampling dengan menggunakan kuadran yang berukuran 1×1 meter. Hasil penelitian menunjukkan bahwa sebanyak 16 spesies bivalvia yang mewakili 12 famili ditemukan di lokasi penelitian, dimana Caloarca tenella menjadi spesies yang paling melimpah. Berdasarkan keanekaragaman Bivalvia yang ditemukan, spesies penyusun saprobik tersusun atas 3 kelompok yaitu Polisaprobik, ꞵ Mesosaprobik, dan Oligosaprobik. Nilai SI berkisar antara -0,50 hingga 1,36 dan TSI berkisar antara 1 hingga 1,96 yang menunjukkan bahwa perairan Desa Lamu berada pada kondisi tercemar ringan sampai berat. The coastal waters of Lamu Village represent one of the potential beaches in Tomini Bay due to their significant biodiversity. Anthropogenic activities in the surrounding coastal areas have the potential to impact water quality through pollution. This study aims to assess the pollution status in the coastal waters of Lamu Village, Gorontalo Regency, using the trophic-saprobic index based on bivalves diversity. The research was conducted from February to May 2024. The study employed a purposive random sampling method using 1×1 meter quadrants. The results showed that 16 bivalvia species representing 12 families were found at the research site, with Caloarca tenella being the most abundant species. Based on the bivalves diversity found, the saprobic species were composed of 3 groups: Polysaprobic, ꞵ Mesosaprobic, and Oligosaprobic. The SI values ranged from -0.50 to 1.36, and TSI values ranged from 1 to 1.96, indicating that the waters of Lamu Village are in a state of light to severe pollution.