The homogenate extraction of limonin respectively by means of the orthogonal design,the uniform design and the response surface methodology ( RSM) ,with the limonin yield,as the evaluation index. Then,by combining the optimal process with the method of crystallization,limonin was extracted from the seeds of oranges ( Citrus reticulata Blanco) in Guangzhou. Moreover,its purity was analyzed through the high-performance liquid chromatography. The results show that the purity of the sample reaches 95%,that the effects of the three statistical methods on the yield are close to each other,and that,by means of RSM,the maximum limonin yield in up to( 6. 65 ± 0. 01) mg /g in the optimal conditions,namely,an ethanol concentration of 71. 7% ( volume fraction) ,a solvent-solid ratio of 28. 8mL /g and a rotating speed of 3953 r /min.