The aims of project work are carried out population dynamics and phylogenetic analysis ofcalanoid copepods from Ennore, Marina and Kovalam (East coast, Tamilnadu) stations. Thediversity of calanoid copepods were studied during October 2018 to September 2019. Thehighest diversity was recorded at Kovalam followed by Marina and Ennore stations. However,highest density was recorded at Marina stations. In the present study, Tortanus forcipatusreported first time in Chennai coast. Taxonomic description of 32 calanoid copepods has beenreported and these characters are used for construction of morphological phylogenetic tree. Apartfrom this, mtCOI and 18s rRNA gene was amplified and sequenced for construction ofmolecular phylogenetic tree. 20 and 15 calanoid species were sequenced on mtCOI and 18srRNA region, respectively. Based on the phylogeny, morphological phylogenetic tree wasconsistent with molecular phylogeny in the super family level. Topologies of morphology, 18srRNA and mtCOI showed clusters of discordance between species levels