This research is aimed to identify kinds of sea grass, frequencies, closing sea grass, essential value index, ecology index (diversity, similarity, domination) and distribution pattern of sea grass in the waters Senggarang Kecil. This research was taken place on Mei 2015 in the waters Senggarang Kecil, Senggarang hamlet, Tanjungpinang Kota district, Tanjungpinang city, Kepulauan Riau province. Survey method was used in this research. Random sampling method was used to determine the point of the sample which it has 41 sampling points. Based on the result of community structure data analysis, there were five kinds of sea grass namely Holophila ovalis, Thalassia hemprichii, Enhalus acoroides, Cymodocea rotundata and Syringodium iseotifolium. The highest frequency was Thalassia hemprichii because it could be seen in all of sampling points. The total of closing sea grass is 11.95 %, the highest essential value index (INP) is Thalassia hemprichii about 92.88, diversity value is 1.95 which is categorized as medium, similarity value is 0.45 which is categorized as medium, and domination value is 0.29 which is categorized as low. The distribution pattern of sea grass in the waters Senggarang Kecil is categorized as horde.
STUDI STRUKTUR KOMUNITAS DAN POLA SEBARAN PADANG LAMUN DI PERAIRAN SENGGARANG KECIL