Abstract: In the work,the by-product bran from purple wheat was used as raw material for the further development and utilization.In this study,the protein of purple wheat bran was extracted by alkali method.The effects of material-liquid ratio,time,pH and temperature on the extraction amount of protein from the raw material were investigated and compared with Kjeldahl method.The extraction conditions of protein were optimized as follows by the single factor experiments:solid to liquid ratio of 1:15,extraction time of 60 min,pH 9 and temperature of 50℃.The experiment was analyzed by SPSS 20.0.The experiments were designed with JMP 11.0 software (data-processing software developed by SAS).The response surfaces of the interaction were drawn by Origin 8.5 software.The extraction amounts of protein from purple wheat bran were used as the responses to establish a mathematical model.The extraction conditions of protein were optimized as follows:the solid-liquid ratio of 1:20,extracting time of 40 min,pH 9.11 and temperature of 60℃.The highest extraction amount of the protein was (66.59 ±0.07) mg/g.