Objective：To investigate whether celecoxib （CXB）, a specific COX-2 inhibitor, can inhibit the proliferation of cyst lining epithelial cells through blocking mitogen-activated protein kinase （MAPK） signal transduction pathway. Methods： Primarily cultured cells were treated with different concentrations of CXB （0,2.5 × 10^- 6 , 5 × 10^-6 , 1 × 10^-5 , 2 × 10^-5 , 3 × 10^-5 , 4 × 10^-5 ,5 × 10^-5 mol/L） and the proliferative status was evaluated by BrdU assay. The levels of vascular endothelial growth factor （VEGF） were measured by enzyme-linked immunosorbent assay （ELISA） ; the production of proliferating cell nuclear antigen （PCNA） and phospho-MAPK were measured by real-time reverse transcription-PCR assay;and the expression of PCNA, MAPK and phospho-MAPK protein was detected by Western blotting. Results： BrdU assay revealed that CXB inhibited cell growth in a concentration-dependent manner; the maximum inhibition rate （[63.9± 1.2] %） was found when cells were treated with 2± 10^-5 mol/L CXB for 24 h. VEGF secretion by cyst lining epithelial cell was reduced by CXB in a concentration and time-dependent manner. The mRNA and protein levels of PCNA, phospho-MAPK in CXB-treated group were lower than those in control group （with no CXB treatment）. Conclusion： CXB can obviously inhibit the proliferation of cyst lining epithelial cell and the secretion of VEGF, which might be through interfering with the phosphorylation of MAPK and partly blocking MAPK signal transduction pathway.