Musashi-1 (Msi-1), a mammalian neural RNA-binding protein, has been found to play important roles in the maintenance of stem cell states and differentiation in neural stem cells and mouse intestinal cells. We explored Msi-1 expression and its potential implications in the human stomach. Reverse transcription-PCR revealed that Msi-1 levels were significantly higher in the corpus than in antrum in Helicobacter pylori (Hp)-infected patients (n = 49) (P < 0.00001) in paired biopsy samples, whereas they were low and comparable at these two sites in Hp-negative patients (n = 31). Msi-1 levels were significantly higher in the Hp-infected corpus (n = 107) than in the Hp-negative corpus (n = 69) (P < 0.00000001). Immunohistochemistry and in situ hybridization demonstrated that Msi-1 was expressed at the base and neck/isthmus region of the fundic glands and partly co-expressed in Ki-67-positive cells in the corpus and antrum. Msi-1 levels correlated with Hp density (P < 0.05). Based on these results, we conclude that Hp infection strongly induces Msi-1 in the corpus. Given its expression in dividing cells, Msi-1 may modulate the state of gastric progenitor cells.