Biofuels are wide range of fuels which are derived from biomass. Biofuels are gaining increases public and scientific attention. Marine algae also known as seaweed are the multicellular plants having potential role in biodiesel production. In this study, Chaetomorpha antennina and Gracilaria corticata were collected from Covelong (East coast of Tamil Nadu) and their diesel content was estimated using different solvent system. Among these species, Chaetomorpha antennina with chloroform-ethanol system produced more diesel content (2.4ml/10gm) than Chaetomorpha antennina with chloroform-methanol solvent system (2.1ml/10gm). Similarly Gracilaria corticata with hexane-ether solvent system produced more biodiesel (2ml/10gm) than Gracilaria corticata with benzene solvent (1.8ml/10gm). The formation of fatty acids of methyl and ethyl esters were also analyzed by GC-MS. GC-MS analysis revealed that the formation of methyl esters was more than the formation of ethyl ester.