Researches have shown that miR-425-5p expression altered in lung, esophageal, and glial cancer. Similarly, in our previous study, we found miR-425-5p expression was up-regulated in GC cells and could promote gastric cancer (GC) cell invasion and metastasis. However, the functional mechanism and the prognostic significance of miR-425-5p in GC remain unclear. Therefore, the present study examined miR-425-5p expression in GC tissues and also evaluated miR-425-5p of the therapeutic and prognostic value. Moreover, with interference of miR-425-5p expression in cell lines, we investigated the molecular mechanism of miR-425-5p and the expression level was higher in GC tissues comparing with that in gastric tumor-adjacent mucosa. These results suggested that miR-425-5p over-expression may be associated with depth of invasion and TNM stages and can be a prognostic marker of poor outcome. After inhibition of miR-425-5p expression in MKN45 cells, the cell activity was weakened. The number of G0/G1 cells increased while G2/M and S cells decreased, and the cell apoptotic rates elevated (P<0.05). Some proliferation and apoptosis related genes were altered (P<0.05). Consequently, miR-425-5p can be considered as a marker of poor prognosis and it is probably involved in GC cell proliferation and apoptosis by regulating some of the genes which participate these processes. (C) 2017 Elsevier GmbH. All rights reserved.