OBJECTIVE To investigate the effects of Wnt3a on epithelial-mesenchymal transition (EMT) in human lens epithelial cells and its molecular mechanisms. METHODS Experimental research. The Wnt3a expression vector was designed and transiently transfected into SRA0104 cells and the PcDNA-HA expression vector was transfected into the controls. The expression of Wnt3a was detected by western blot analysis. The expression of β-catenin was detected by western blot analysis and the location of β-catenin was detected by immunofluorescence assay. The expression of E-cadherin protein as epithelial biomarker and fibronectin protein as mesenchymal biomarker was detected by Western blot analysis. The mobility of SRA0104 cells was assessed by scratch assay and transwell assay in vitro. Statistical significance was determined by Student's t-test. RESULTS The Wnt3a/SRA/01/04 cells were obtained by transfection of wnt3a cDNA expression vector in SRA01/04 cells and the pcDNA3-HA/SRA01/04 cells were used as the controls. The Wnt3a cDNA expression vector triggered β-catenin as a transcriptional activator accumulated and translocated into the nucleus, which induced the decreasing expression of E-cadherin proteins and increasing expression of fibronectin protein, and resulted in EMT in lens epithelial cells. Wound healing assay in vitro showed that the migration distance of Wnt3a/SRA01/04 cells was (0.36 ± 0.02) mm at 24 hours after scratch, significantly increased as compared to the control cells (t = 21.98, P < 0.01). After 48 hours of incubation in transwell migration assay, the number of migratory cells across polycarbonate membrane in Wnt3a/SRA01/04 cells was 92.25 ± 10.34, which was much more than the control cells (t = 10.40, P < 0.01). The mobility and migration of Wnt3a/SRA01/04 cells was increased. CONCLUSIONS Wnt3a activates Wnt/β-catenin signaling pathway, induces EMT in lens epithelial cells and then increases mobility and migration of lens epithelial cells.