NOVELTY - Method for culturing Scenedesmus strain SDEC-13 and recycling sewage using culture, involves (a) culturing the Scenedesmus strain SDEC-13 using blueGreen (BG)-11 enriched culture medium, (b) adding culture to bioreactor containing sewage, (c) performing culturing process at 24-30 degrees C for 16 days, (d) centrifuging obtained culture, and freeze-drying and centrifuging product, (e) processing sewage with supernatant, performing step (b), and then performing culturing process at 24-30 degrees C for 10 days, and (f) centrifuging and freeze-drying product.    USE - The method is useful for culturing Scenedesmus strain SDEC-13 and recycling sewage using culture (claimed).    ADVANTAGE - The method is convenient and cost-effective to perform, provides nutritional substance required by culture, and produces biomass having high quality protein and lipid.    DETAILED DESCRIPTION - Method for culturing Scenedesmus strain SDEC-13 and recycling sewage using culture, involves (a) culturing the Scenedesmus strain SDEC-13 using blueGreen (BG)-11 enriched culture medium, (b) adding 0.76x 106 cells/ml of culture obtained in step (a) to bioreactor containing sewage, where absorbance of culture is 0.2 at 688 nm, where biomass concentration of the culture is 0.11 g/l biomass, (c) placing the bioreactor in chamber, and performing culturing process at 24-30 degrees C for 16 days, and maintaining illumination at 2000-4000 lx and controlling aeration rate at 180-230 ml/minute during culturing process, (d) centrifuging culture obtained in step (c) to obtain biomass, freeze-drying obtained product for 20 hours, centrifuging obtained product, and collecting supernatant, (e) processing sewage with the supernatant, performing above-mentioned step (b), and then performing culturing process at 24-30 degrees C for 10 days, and maintaining illumination at 2000-4000 lx and controlling aeration rate at 180-230 ml/minute during culturing process, and (f) centrifuging culture obtained in step (e) to obtain biomass, and freeze-drying obtained product for 20 hours to obtain powder.