Gastric cancer (GC) is one of the major causes of cancer deaths with 5-year survival ratio of 20%.RNU12is one of long noncoding RNAs (lncRNAs) regulating the tumor progression. However, how RNU12 affecting GC is not clear. qRT-PCR was utilized for determining theRNU12expression in cell lines, 113 cases of paired gastric cancer (GC) and their adjacent normal gastric tissues. The biofunction alterations ofRNU12were assessed by its overexpression or knockdown in GC cells. MTT and cloning assay were assayed for the cell proliferation, the flow cytometry for the detection of cell cycle and the wound healing assay (WHA) and transwell invasion assay (TIA) for examining the migration and invasion of cells. The expressions of a set of genes related proliferation and migration were investigated with the Western Blotting (WB). RNA immunoprecipitation (RIP), biotinylated RNA pull-down and dual luciferase reporter tests were used to detect the interactions ofRNU12with miR-575/BLID. The in vivo proliferation and migration ability ofRNU12infected cells were determined in zebrafish system. This study revealed thatRNU12inhibited proliferation, invasion and metastasis by sponging of miR-575 and regulating the downstream BLID and modulated EMT of GC cells. TheRNU12/miR-575/BLID axis is likely to be the prognosis biomarkers and drug targets of GC.