Abstract: To extract pigment by using supercritical CO2 fluid extraction of brewer's grains, on the basis of single factor experiment, with extraction temperature, extraction pressure, CO2 flow rate as the key factor, the pigment extraction yield as response values, through the response surface analysis, determineing the optimum technological parameter of the key factors:the extraction temperature was 45℃, extraction pressure for 30MPa, the CO2 flow rate was 30L/h, the extraction time was 150min, in the end, the content of the pigment yield achieved 65.9μg/g.