Abstract: The extraction of protein from the sloanea hemsleyana seed by alkaline extraction and acid precipitation was studied. According to the single-factor experiments, three levels of the factors (extraction temperature, extraction time, pH and material/liquid ratio) were selected for the central composite design to establish a quadric regression equation for describing the yield of sloanea hemsleyana seed protein. By response surface analysis, the optimum extraction conditions were obtained as follows:extraction temperature of 42℃, time of 138min, pH9.6 and material/liquid ratio of 1∶25 (g/mL) , under which the highest yield of sloanea hemsleyana seed protein reached 64.97%.