Objective  To study the expression of long non-coding RNA(lncRNA) maternally expressed 3(MEG3) in urothelial carcinoma and the molecular mechanism of MEG3 mediating cell proliferation activity.Methods  Real-time fluorescence quantitative PCR(RT-PCR) was used to detect the expressions of MEG3 in urothelial carcinoma and normal adjacent tissues. The level of and gene of phosphate and tension homology deleted on chromosome ten(PTEN) in T24 cells after overexpressing lncRNA MEG3 was detected by Western blot. And the cell proliferation activity was determined by CCK8 kit. Results  The expression of MEG3 was significantly downregulated in urothelial carcinoma tissues(P<0.01), and the expression of PTEN was also significantly downregulated(P<0.01). After overexpression of MEG3 in T24, the level of PTEN increased and the cell activity decreased(P<0.01). And when PTEN inhibitor was given the same time, the cell activity increased.Conclusions  Overexpression of lncRNA MEG3 can inhibit the proliferation of human urothelial carcinoma cell line T24 by upregulating PTEN, which may become a potential target for clinical treatment.