目的：提取分离泥螺软体组织，探索其体外抗肿瘤活性。方法：采用胰蛋白酶酶解法获得泥螺多肽粗提物，通过超滤膜滤过技术获得分子量在5~10 kDa的组分。用葡聚糖凝胶G-75分离、纯化，MTT法测定其体外抗肿瘤活性并用荧光染色法观察细胞形态。结果：经膜分离得到的组分(分子量5~10 KD)和经葡聚糖凝胶G-75分离得到的泥螺多肽对前列腺PC-3肿瘤细胞均有一定的抑制作用，且后者强于前者。结论：泥螺多肽具有一定的抗前列腺PC-3肿瘤细胞的活性。 Objective: To isolate and purify the peptide from Bullacta exarata, and study its anti-tumor effect on prostate cancer. Methods: The antimicrobial peptides were hydrolyzed from soft tissues of Bullacta exarata by trypsin, and purified by sephadex chromatography. Measured by MTT assay in vitro anti-tumor activity and cell morphology was observed by fluorescence staining. Results: The components separated from membrane (molecular weight 5 - 10 KD)and isolated by the Sephadex G-75 could inhibitse the PC-3 cells growth, and the latter stronger than the former. Conclusion: The Bullacta peptides could inhibitse the PC-3 cells growth and have anti-tumor activities on prostate cancer.