Further cellular study confirmed that monobenzone could inhibit the proliferation of gastric cancer cell lines MGC-803 and BGC-823 with IC50 as 7.82 ± 0.55 μM and 6.99 ± 0.51 μM, respectively, and erase the substrate of KDM1A, H3K4me1/2 and H3K9 me2, and inhibit the migration of gastric cancer cell by reversing epithelial–mesenchymal transition (EMT). This evidence concerns the gene KDM1A and gastric cancer.