The research had been done on September-November 2011 in The Dompas Village, Bengkalis Regency, Riau Province. The purpose of this research is to understand the relationship among the density of mangrove, litter production and the abundance of Terebralia sulcata. There were 4 stations and 3 plots in each station. Mangrove density and T. sulcata abundance were studied once, while litter pro…