As we know, the marine resources are important and have nutritive values to the human being. In this present study to reveal the quantity of shrimps and crabs landed in Poompuhar fish landing centre, Mayiladuthurai District, Tamil Nadu during from January 2016 to December 2016. Fortnightly the data were collected in the fish landing center and weighed itself. The average was calculated from 11 months of study period due to the fishing ban period occurs during from April 15th to June 15th of every year. Meanwhile the data were incorporated the balance month of April and June also. The results showed that, the average landing of shrimps per month was calculated that Penaeus monodon was high and least was Aristeus alcocki. In crabs, Portunus sanguinolentus was high and least was recorded Podaphthalamus vigil and Charybdis truncate. The month wise calculation was made to know the quantity of shrimps was landed in Poombuhar fish landing site during the study period. In December showed that, high amount of shrimps landed and the least amount of shrimps was landed during the month of August. In case of Crabs showed that, high amount of crabs landed during October and the least amount of crabs was landed during the month of April. It concluded that, the fishing equipments like fishing net, fishing vessels and experience of fisherman which directly influence to the fish quantity in the landing sites of Tamil Nadu.

Keywords : Shrimps, Crabs, Quantification, Poompuhar fish landing center, Decopods.