Taking the mung beans as raw materials, the Osborne classification method was used to extract albumin from mung bean. Based on the single factor test, using the L₉ (3⁴) orthogonal test, the effects were studied, from the extraction temperature, extraction time and ratio of material to liquid on the extraction rate of mung bean albumin. The subunit composition of mung bean albumin was analyzed by SDS-PAGE. The results showed that the optimal extraction process of mung bean albumin were: ratio of solid to liquid of 110 (g/mL), extraction temperature of 45 ℃, extraction time of 150 min. Under this condition, the extraction rate of mung bean albumin was (84.79±0.31)%. The purity of the albumin was 88.33%. There are 4 subunit bands in the extracted mung bean albumin. The molecular weights of the 4 subunit were 56.2, 46.8, 26.3, and 21.9 kD, respectively.