Ahadi A., et al. - To confirm whether microRNAs (miRNAs) can be potential biomarkers in gastric cancer (GC) diagnosis and prognosis, this systematic review of published miRNA studies in GC with miRNA expression profiles between GC tissues and normal tissues. In these studies, miR-21, miR-106b, miR-25, miR-214, miR-18a, miR-191, and miR-93 were upregulated and miR-375, miR-148a, miR-92, miR-155, and miR-564 were downregulated in GC tissues. In assessing the diagnostic ability of miRNAs, an analysis conducted on a combined miRNA including miR-21, miR-93, miR-106a, and miR-106b suggested these had the highest AUC (0.887) for distinguishing GC patients from healthy ones. In GC patients, poor survival could be predicted by miR-21. The data from this systematic review supports the need to discover a miRNA or a panel of miRNAs with high sensitivity and specificity for further exploration to define a better diagnostic or therapeutic instrument for personalized management of GC patients.