Abstract: In order to study the possibility of the production of natural edible pigment chlorophyll from green microalgae,and to investigate the procession conditions of that production,the effects of nitrogen source contents in the medium on the chlorophyll content of the microalgal cell were investigated,and the effects of the solvent formulas, solvent quantities, extraction time, extraction temperature and ultrasonication on the chlorophyll extraction were studied. The results indicated that a satisfied extract rate could be obtained when 8times of a complex solvent composed of acetone and ethanol at a ratio of 1∶3 based on the microalgal biomass was utilized and the extraction was performed at 45℃ for 8h. At that procession conditions,53.69mg/g(by dry cell weight) of chlorophyll had been extracted from the green microalga Neochloris oleoabundans.