Abstract: Single-factor experiment and orthogonal experiment were used to optimize the extraction technology of white kidney bean albumin, and the isoelectric point and molecular composition of albumin were analyzed. The results showed that the isoelectric point of albumin was 3.5. The optimized conditions of the albumin extraction process were as follows: solid-liquid ratio 1∶8 ( g /mL) , extraction temperature 55℃, extraction time 3h, and the ratio of albumin extraction was 37.93% under the above conditions.SDS-PAGE electrophoretic analysis results showed that there were five protein subunit bands when the extracting solution of albumin was placed at 10℃ and 20℃.But there were only two protein subunits ( 35.31 ku and 30.52ku) when the extracting solution of albumin was placed at4℃, and the 35.31 ku protein subunit might be α-amylase inhibitor.