Objective:To establish the expression profiles of peptides in sera of ovarian cancer and explore the early-diagnosis value of expression profiles of peptides in ovarian cancer. Methods:Magnetic binding-weak cation exchange beads (MB-WCX) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis were used to detect expression files of peptides. The early-diagnosis pattern was established by differential peptides peaks using the ClinProTool data analysis program. Results:In the mass range from 1 000 to 15 000 Da,8 peaks with clear differences in amplitude between the patients and health controls were detected,5 peaks with mass charge ratio(m/z) of 2 662.02, 2 653.68,5 859.21,5 901.69 and 5 937.06 were up-regulated notably,and 3 peaks with m/z of 1 857.82,2 074.28 and 2 856.33 were markedly down-regulated in patients with ovarian cancer. In specimens of early-stage ovarian cancer,the accuracy of characteristic proteomic patterns detection could be 81.8%(9/11),and the specificity showed 100%. Conclusion:MB-WCX separation coupled with MALDI-TOF-MS and ClinProTools analysis could be a desired method to find bio-markers in ovarian cancer,and could have a potential value in the early diagnosis of ovarian cancer.