Long non-coding RNAs (lncRNAs) have been demonstrated that it plays very important role in development and progression of carcinomas. LncRNA FEZF1 antisense RNA 1 (FEZF1-AS1) has been proved to be implicated in tumor initiation and progression of various cancers, recently. Nevertheless, the biological function and clinical significance of lncRNA FEZF1-AS1 in gastric cancer (GC) are not clear enough. Here, we concentrated on the association of FEZF1-AS1 expression and clinicopathological factors in GC tissues and cells. Moreover, we explored the potential regulatory mechanisms. The results showed that lncRNA FEZF1-AS1 was observably upregulated in human GC tissues and GC cell lines, compared with the adjacent non-tumor tissues and human gastric epithelial cell line (GES-1). Moreover, high expression of lncRNA FEZF1-AS1 was significantly associated with later stage and higher grade. Furthermore, Kaplan-Meier survival analysis was conducted, indicating that lncRNA FEZF1-AS1 may be an independent prognostic factor in GC. Additionally, the area under the receiver operating characteristic (ROC) curve of lncRNA FEZF1-AS1 exhibited its diagnostic value in GC. Notably, whenever the lncRNA FEZF1-AS1 was silenced, the proliferation of GC cells were significantly inhibited and the cell cycle was arrested at a G0/G1 stage in GC cells. Furthermore, downregulation of lncRNA FEZF1-AS1 could suppress the activation of the Wnt/β-catenin signaling pathway. Conclusively, our findings indicated that lncRNA FEZF1-AS1 could be considered as a novel biomarker for the treatment of GC.