To investigate the roles and underlying mechanisms of vascular endothelial growth factor receptor-3 (VEGFR-3) in gastric cancer (GC). VEGFR-3 gene expression profiles in human gastric adenocarcinoma (GAC) tissues were analysed using The Cancer Genome Atlas database. Human GC cell lines and were used for in vitro studies. Mouse models of GC and distant metastasis were used for in vivo studies. Silencing of VEGFR-3 gene expression was achieved using small interfering RNA. VEGFR-3 gene expression was significantly elevated in GAC tissues and GC cells. Higher VEGFR-3 expression was positively correlated with more advanced stages and a greater number of metastatic lymph nodes. In vitro studies in GC cells showed that knockdown of VEGFR-3 gene expression significantly suppressed cell proliferation and migration, but promoted apoptosis. In vivo investigations revealed that silencing of VEGFR-3 gene expression exhibited significant inhibition on tumour growth and metastasis. Further mechanistic studies showed that VEGFR-3 exerted its pathological roles by affecting the key molecules in the apoptotic and epithelial-mesenchymal transition pathways. The molecular pathways associated with VEGFR-3-mediated pathological effects could be targets in the development of novel approaches for the diagnosis, prognosis and treatment of GC.