A method for extracting recombinant human serum albumin (rHSA) from transgenic rice grain is provided, comprising the steps of: 1) grinding dehusked rice containing rHSA into milled rice grain with a fineness of 80&tilde；120 mesh, which is mixed with a extraction buffer in a w/v ratio of 1:5, then extracting at 55&tilde；60° C. for 1&tilde；3 hours to obtain mixture I； said extraction buffer comprises 10&tilde；30 mM phosphate buffer, 10&tilde；20 mM sodium acetate, 15&tilde；30 mM ammonium sulfate and 5&tilde；20 mM sodium caprylate and has a pH of 6.5&tilde；8； 2) adjusting the pH of mixture I to 4.0&tilde；4.5, followed by precipitating at room temperature for 3&tilde；12 hours to obtain mixture II； 3) filtering the mixture II and collecting the filtrate, to obtain a solution containing high concentration of rHSA. The concentration of rHSA in the resultant solution is 650&tilde；660 &mu；g/mL, which increases by 1.15 times comparing to the extraction amount before improvement, and the amount of non-target protein is reduced by 2.46 times. The method provides a basis for subsequent purification of rHSA.【課題】組換えヒト血清アルブミン（ｒＨＳＡ）のさらなる精製のための基礎を提供する。【解決手段】本発明は、トランスジェニックイネの子実からヒト血清アルブミンを抽出する方法を提供し、当該方法は、脱殻済みのイネを砕き、砕いたイネの子実を抽出用緩衝液と混合し、攪拌しながら抽出して混合物Ｉを得るステップ（１）と、混合物ＩのｐＨを４．０～４．５に調整し、１～１２時間沈降させて混合物ＩＩを得るステップ（２）と、混合物ＩＩを濾過し、濾過液を集めて高濃度のヒト血清アルブミンを含有する溶液を得るステップ（３）とを含む。【選択図】なし
