Increasing evidence has indicated that long non‑coding RNAs (lncRNAs) were aberrantly expressed and acted as key regulators in various types of disease, including cancer. lncRNA cancer susceptibility 2 (CASC2) has been found to be downregulated and acts as a tumor suppressor in various type of cancer, including gastric cancer (GC). However, the precise function of lncRNA CASC2 in GC remains unclear. In the present study, the expression level of lncRNA CASC2 in GC was investigated and the molecular mechanisms by which CASC2 acted as a tumor suppressor in this disease were elucidated. It was found that the expression level of lncRNA CASC2 was decreased, which correlated with TNM stages, vessel invasion, metastasis, and overall survival of patients with GC. Furthermore, overexpression of CASC2 inhibited the invasion and angiogenesis of GC cells. Thus, the present study indicated the important roles and underlying molecular mechanisms of lncRNA CASC2 on GC, and indicated that lncRNA CASC2 may present as a potential therapeutic target for the treatment of GC.