This research was conducted in November 2015 in the waters of Karimun Besar Island Province of Riau Islands. A research aims to analyze macrozoobenthos density, sediment organic matter and analyze a correlation between sediment organic matter and macrozoobenthos density. Samples were collected from 3 stations, each station consists 3 plots. Each plot split into 16 sub plots, from 16 sub plots w…