OBJECTIVE: To explore the relationship between Helicobacter pylori (Hp) infection and the gastric mucosa and serum interleukin-8 (IL-8) levels in children so as to study the role of IL-8 in Hp-related gastrointestinal diseases. METHODS: Fifty-three children with recurrent upper abdominal pain or other related complaints were given endoscopy inspection. The gastric mucosa was collected for Hp qualitative detection by both rapid urea enzyme test and histopathologic examination. The gastric and serum IL-8 levels were detected using ELISA. RESULTS: Hp infection was confirmed in 29 children. The gastric IL-8 level in children with Hp infection ( 32.86± 3.92 pg/mg) was significantly higher than that of children without Hp infection ( 13.75± 2.19 pg/mg) (P< 0.01). There was no difference in serum IL-8 level between them. After the treatment of Hp infection, the gastric IL-8 level in children with Hp infection decreased significantly ( 15.91± 3.15 pg/mg) (P< 0.01), while serum IL-8 level of children with Hp infection was not different before and after treatment. CONCLUSIONS: Hp infection can induce the inflammatory cells of the gastric mucosa to secrete IL-8. IL-8 may play an important role in the pathogenesis of Hp-related gastrointestinal diseases.