In this study,response surface methodology was used to optimize the ultrasonic-assisted ionic liquid extraction method to extract buckwheat hull pigment,and its stability and antioxidant activity were studied.In the experiment,amino acid ionic liquid was synthesized,L-lysine phosphate ionic liquid was screened out,and pigment was extracted from buckwheat hull.The effects of the concentration ofL-lysine phosphate ionic liquid,solid-liquid ratio,extraction time and extraction temperature on the pigment were investigated.The optimum extraction process was determined by single factor test and response surface methodology.The concentration of L-lysine phosphate ionic liquid was 14%,the solid-liquid ratio was 1∶22,the extraction temperature was 80 ℃,and the extraction time was 45 minutes.This study clarified the best extraction process of buckwheat hull pigment,and laid a certain foundation for the industrial extraction of buckwheat hull pigment.