The ornamental shell industry in India in recent years is a multimillion dollar industry. India’s ornamental trade is currently worth US$ 278 million. The collection of molluscan shells is a popular activity in coastal areas. Ornamental molluscs are sold in the market exclusively for aquarium and ornamental purposes. Molluscan shells are used in studs like ear-rings, bangles, table lamps, spoons cups and saucers etc., and it is also used in Aquarium. A study was carried out on ornamental molluscan resources of Tamil nadu coast to identify, quantify and assess the shell resources potential for development of a small-scale shell industry and also a suitable collection techniques and methods of shell catalogue preparation during Oct 2007 to Sep 2008. Gastropods and bivalves have been collected for ornamental purpose by the fisher folks. During the survey gastropods and bivalve species belonging to 21families such as Turritellidae, Cypraeidae, Volutidae, Muricidae, Conidae, Trochidae, Olividae, Cassidae, Marginellidae, Bursidae, Strombidae, Buccinidae, Naticidae, Tonnidae, Melongenidae, Vassidae, Harpidae, Architectonidae Arcidae, Pectinidae, Veneridae, were collected. From the total molluscan diversity 85% were exclusively ornamental molluscs. The study revealed that the occurrence of gastropods and bivalves species here are most valuable shells and naturally rare and not easily available.