Helicobacter pylori (HP) infection induces the development of gastric carcinoma (GC), one of the most frequent and fatal cancers worldwide, via a progressive cascade. The roles of microRNAs (miRNAs) involved in the cascade and the behind mechanisms, however, are still unclear. This study was designed to investigate the expression of miR-650, a well-recognized oncogenic miRNA in GC samples and to analyze the associations between this miRNA and HP infection, and the molecular mechanism. Following miRNA- and mRNA-based microarray analyses, miR-650, pre-B-cell leukemia transcription factor 1 (PBX1), and LATS2 were filtered as targets. After that, function assays were implemented to assess their function in GC cells. miR-650 was upregulated in HP+ tissues and cells, and inhibition of miR-650 attenuated cell proliferation, invasion, migration, yet enhanced apoptosis. PBX1 was overexpressed in HP+ tissues and cells and promoted miR-650 transcription. Overexpression of PBX1 abrogated the effect of the miR-650 inhibitor on GC cells. miR-650 targeted LATS2, and LATS2 was poorly expressed in HP+ tissues and cell lines. Simultaneous knockdown of miR-650 and LATS2 reduced GC cell apoptosis. These results display that upregulation of miR-650 induced by HP infection and PBX1 dampens LATS2 in GC cells, potentially offering novel intervention targets for GC.