Abstract: Objective To investigate effects of cyclooxygenase-2 selective inhibitor on the expression of VEGF-C and bcl-2 mRNA in human prostate cancer PC-3 cell lines,and study the anticancer mechanism of COX-2 selective inhibitor. Methods The PC-3 cells were divided to four groups:Test groups(The cells were treated with celecoxib at different concentrations-10 μmol/L,20 μmol/L,40 μmol/L) and control group(celecoxib was not used),detected the expression of VEGF-C and bcl-2 mRNA in the four groups by RT-PCR method. Results 　There were no statistical difference of the VEGF2C/ GAPDH and bcl22/ GAPDH value between 10 μmol/ L celecoxib group and cont rol group ( P > 0. 05) ;VEGF2C/ GAP2 DH value in 20μmol/ L and 40μmol/ L celecoxib groups were 0. 370 ±0. 063 and 0. 263 ±0. 062 respectively, bcl22/ GAPDH value in both the groups above were 0. 339 ±0. 047 and 0. 272 ±0. 042 respectively, both the value above in the two groups decreased significantly compared with cont rol group ( P <0. 01) . Conclusion 　Celecoxib maybe plays it s antitumor effect by inhibiting the expression of VEGF2C and bcl22 mRNA in prostate cancer PC23 cell lines.