ABSTRAK : Desa Kaliwlingi dan Sawojajar mempunyai kawasan hutan mangrove dengan karakteristik berbeda. Kawasan hutan mangrove Kaliwlingi menjadi ekowisata mangrove sejak tahun 2016, sedangkan di Sawojajar merupakan kawasan mangrove alami. Perbedaan fungsi tersebut diduga dapat mempengaruhi keanekaragaman hayati yaitu salah satunya adalah gastropoda. Tujuan dari penelitian ini adalah untuk mengetahui struktur komunitas Gastropoda di ekosistem mangrove Desa Kaliwlingi dan Sawojajar, Kab.Brebes, Jawa Tengah. Pengambilan sampel dilakukan pada bulan Juni sampai Juli 2018. Penentuan titik sampling menggunakan metode purposive pada 3 stasiun dengan tiga kali pengulangan. Hasil penelitian menunjukan terdapat 2 subkelas yaitu Pulmonata dan Prosobranchiata, dengan 3 famili dan 9 spesies gastropoda dari 3 famili, yaitu Elliobidae; Cassidula aurisfelis (Elliobidae), C. nucleus (Elliobidae), Littoraria articulate (Littorinidae), L. carinifera (Littorinidae), L. melanostoma (Littorinidae), L. scabra (Littorinidae), Telescopium telescopium (Potamididae), Terebralia obtuse (Potamididae), T. palustris (Potaminidae). Nilai kelimpahan rata-rata gastropoda Desa Kaliwlingi dan Desa Sawojajar masing-masing 20,28 dan 16,36 Ind/m². Indeks Keanekaragaman (H’) gastropoda di kawasan mangrove Desa Kaliwlingi dan Desa Sawojajar termasuk ke dalam kategori rendah ke tinggi, sedangkan indeks keseragamannya berkategori rendah. Tidak ada jenis gastropod yang mendominasi di kawasan mangrove Kaliwlingi dan Sawojajar, dengan pola sebaran gastropoda mengelompok.ABSTRACT: Kaliwlingi and Sawojajar villages have mangrove forest areas with different characteristics. The Kaliwlingi mangrove forest area has been established as mangrove ecotourism since 2016, while in Sawojajar it is a natural mangrove area. The difference in function is thought to affect biodiversity, one of which is gastropods. The purpose of this study was to determine the structure of the Gastropoda community in the mangrove ecosystems of Kaliwlingi and Sawojajar Villages, Kab. Brebes, Central Java. Sampling was conducted in June to July 2018. Determination of the sampling points using purposive methods at 3 stations with three repetitions. The results showed that there were 2 subclasses, namely Pulmonata and Prosobranchiata, with 3 families and 9 gastropod species from 3 families, namely Elliobidae; Cassidula aurisfelis (Elliobidae), C. nucleus (Elliobidae), Littoraria articulate (Littorinidae), L. carinifera (Littorinidae), L. melanostoma (Littorinidae), L. scabra (Littorinidae), Telescopium telescopium (Potamebidide) ), T. palustris (Potaminidae). The mean abundance of gastropods in Kaliwlingi Village and Sawojajar Village were 20.28 and 16.36 Ind / m² respectively. Diversity Index (H ') of gastropods in the mangrove areas of Kaliwlingi Village and Sawojajar Village are in the low to high category, while the uniformity index is categorized as low. There is no type of gastropod that dominates in the Kaliwlingi and Sawojajar mangrove areas, and gastropod distributed as a grouped.