【Abstract】 Objective To explore the expression of cancerous inhibitor of protein phosphatase 2A (CIP2A) in ovarian cancer tissues and its effects on tumor cell invasion and migration after gene silencing. Methods The ovarian cancer tissues and normal ovarian tissues preserved in our hospital were collected, and the expression level of CIP2A in tissues was determined. siRNA was used to interfere with the expression of CIP2A in ovarian cancer cell lines A2780 and SKOV3, and the cells were divided into control group and interference group. The cell proliferation in the two groups was detected by MTT assay, and Transwell was used to detect the cell invasion and migration ability in the two groups, and Western Blot was used to detect the expression levels of Ecadherin (Ecad), matrix metalloprotein (MMP)2, MMP9, metastatic tumor antigen 1 (MTA1) proteins. Results Compared with normal ovarian tissues, the expression levels of CIP2A protein and CIP2A mRNA in ovarian cancer tissues were significantly increased (P＜0.05). Compared with control group, the proliferation rate, invasion and migration of A2780 and SKOV3 cells in interference group were significantly decreased (P＜0.05), and the protein expression of Ecad was significantly increased (P＜0.05), and the protein expression levels of MMP2, MMP9 and MTA1 were significantly decreased (P＜0.05). Conclusion CIP2A has high expression in ovarian cancer tissues, and it can effectively regulate the expression of related proteins of cell invasion and migration, and regulate cell invasion and migration.