This study aimed to assess ecological large communities benthoses mollusk in tidal coastal city of Bushehr, has been done. Sampling from autumn 2012 to summer 2013 and was carried out over 4 seasons. A total of five stations, including two sandy bed of Raphael and Bandargah, and three rocky Naftkesh, Shoghab and Heleyleh were selected for sampling. Sample by using Quadrat 50 × 50 cm and by knife metal were collected and then sent to the laboratory using identification keys and identification were studied. Bold and the tiniest grain of sand beaches, respectively Raphael station with 0.34 and 22.77% was measured. Water quality parameters for temperature range of 21.5 to 36.5 ° C and 39.1 to 45 ppt salinity, dissolved oxygen ranges from 1 to 6.3 mg and pH between 7.3 to 8.9 were measured. During laboratory operation, a total of 29 species of mollusk belonging to three Keywords : Mollusc Macrobenthic Organisms, Tidal Zone, Diversity index, Dominance index.
