Abstract: The present paper study is on fresh water microalgae from region of Ahmednagar district in Maharashtra. Fresh water microalgae are modern biomass for the production of biodiesel fuel due its faster growth, highest biomass productivity and high lipid content with various conversion methods into biofuel. The biodiesel has very mimic property like petroleum diesel. The study emphasis on fresh water algae strain in the class of Chlorophyceae and Chlorococcum humicola species isolated and convert it into biodiesel by base catalysed transesterification method. The chemical properties of product analyze by standard method Infrared spectroscopy and Gas Chromatography Mass Spectroscopy.