The application provides a method for preparing rubusoside comprising steps of raw material crushing, flash extraction, double centrifugations, macroporous resin purification, desorption, enzymatic hydrolysis, organic film decoloring, concentration, crystallization and drying. The application optimizes the quality control of key process such as extraction, separation, purification and decolorization, and can obtain the rubusoside product with purity more than 99%, and the product is white, no bitterness, less solvent residue, no pesticide residue, and stable quality.