Candida-associated gastric ulcer occurs not only in debilitated but healthy individuals. Though had been reported to demonstrate nothing but nonspecific endoscopic features, it occasionally exhibits a typical finding I designated a candidarium. The natural history of the disease had not been clarified and the recurrence had not been described. However, I demonstrated that the ulcer not only occurs but also recurs in a different site with a different shape in a non-diabetic, H. pylori-negative patient, who has not taken NSAIDs, antibiotics, antineoplastic agents, or systemic corticosteroids, advocating that, contrary to the prevailing opinion, Candida is no innocuous bystander but an etiologic perpetrator. It has recently been shown to secrete a cytolytic PFT, candidalysin, into a pocket in the epithelium after penetrating into it to activate MAPK/MKP1/ c-Fos pathway, triggering release of damage as well as immune cytokines in OPC and VVC. While candidalysin, exerting an effect even on the adjacent oropharyngeal cells, directly injures the tissue with damage cytokines, immune counterparts activate PMNs to eventually terminate inflammation. Though the epithelial response to the fungus is different from organ to organ, it invades into and induces necrotic cellular damage to the IECs through the toxin to translocate: the action of candidalysin is proven not only on the squamous but on the columnar epithelium. Since, by analogy with intestinal candidiasis, it is never difficult to speculate that the PFT inflicts such damage to the gastric mucosa, a theoretically strong possibility has come up that Candida-associated gastric ulcer is actually Candida-induced.