OBJECTIVE: To study the relationship of Helicobacter pylori (H. pylori) infection with the development and relapse of Henoch-Schonlein purpura (HSP) with gastrointestinal involvement in children. METHODS: Thirty-six HSP children with gastrointestinal manifestations and 16 of 32 HSP children without gastrointestinal involvement underwent gastroscopy and rapid urease test for H. pylori detection. Thirty healthy children served as the control group. All of the patients received 14C urea breath test and serum H. pylori antibody detections. H. pylori infection was definited when two of detection approaches demonstrated positive. RESULTS: Twenty-one of 36 HSP patients with gastrointestinal manifestations were confirmed with H. pylori infection (58.3%). Of them, the relapsed patients had an H. pylori positive rate of 81.3% (13/16), which was significantly higher than that of the newly diagnosed patients （45.0%，9/20) (χ2=4.49, P<0.05). Nine of 32 HSP patients without gastrointestinal manifestations were confirmed with H. pylori infection (28.1%); 2 of 30 healthy children showed H. pylori positive （6.7%, 2/30). There was a significant difference in the H. pylori positive rate among the three groups (χ2=14.7, P<0.01). CONCLUSIONS: H.pylori infection may be associated with the development and relapse of HSP with gastrointestinal involvement in children.［Chin J Contemp Pediatr, 2007, 9 (4):367-369］