Galectin-3, a β-galactoside-binding lectin, is a cell adhesion molecule involved in the regulation of tumor progression. However, the importance of galectin-3 in Eca-109 human esophageal cancer cells has not yet been elucidated. In the present study, a lentiviral vector was designed for overexpression of galectin-3 in Eca-109 cells following plasmid‑mediated transfection (Eca-109/Gal-3 cells). A negative lentiviral vector was introduced into Eca-109 cells as a control (Eca‑109/Neo cells). Western blot and reverse transcription-polymerase chain reaction analyses were used to measure the expression levels of galectin-3 protein and mRNA. The proliferation of Eca-109 cells was measured by a cell counting kit-8 assay. Eca-109 cell apoptosis was determined by Annexin V/7-amino-actinomycin double‑staining. The migration and invasion capacity of Eca-109 cells was determined by a Transwell assay. A total of >98% Eca-109 cells were transfected with the lentiviral vector harboring galectin-3, and galectin-3 expression was detected in Eca-109 cells, Eca-109/Gal-3 cells and Eca-109/Neo cells. Compared with non‑transfected and negative control Eca-109 cells, proliferation was increased significantly in the Eca-109/Gal-3 cells (P<0.05). Galectin-3 also significantly reduced Eca-109 cell apoptosis, compared with the two control groups (P=0.007 and P=0.04, respectively). Transwell migration and invasion assays revealed that significantly greater numbers of Eca-109/Gal-3 cells crossed the artificial basement membrane (55.4±3.9) compared with either the non-transfected or negative control Eca-109 cells (30.6±1.5 and 29±2.6 respectively, P<0.05). In conclusion, galectin-3 expression was significantly increased in transfected Eca-109 esophageal cancer cells, resulting in enhanced proliferation, migration and invasion, as well as reduced apoptosis. These data indicate that galectin-3 may be a potential molecular target in the treatment of esophageal cancer.