Abstract: Objective 　To study the expression of Matrix Metalloproteinase-9 (MMP-9) and Tissue inhibitor of metalloproternase-1 ( TIMP-1) in epithelial ovarian tumor and their clinical significance. Methods 　The expressions of MMP-9 and TIMP-1 in 94 cases of epithelial ovarian tumor were determined by tissue microarray combined with immunohistochemistry. Results 　The positive rates of MMP-9 in borderline and ovarian adenocarcinoma tissue were significantly higher than that in benign tumor tissue ( P < 0. 01) . The positive rate of TIMP-1 in ovarian adenocarcinoma tissue was also significantly higher than that in benign tumor tissue ( P < 0. 01) . The expressions of MMP-9 and TIMP-1 weren'trelated to patients'age, tumors' size and histologic types, but with histologic grade, the proportionality of MMP-9/ TIMP-1 increased obviously with growing malignant potential of ovarian adenocarcinoma. Conclusion 　The expression of MMP-9 and TIMP-1 may play an important role in the development of malignant epithelial ovarian tumor, which may serves as a marker for diagnosis in borderline and ovarian adenocarcinoma. Tissue microarray is an efficient, low consume and strong comparability technique in study of human pathology.