Some studies have suggested that low-grade MALT lymphoma may regress after eradication of Helicobacter pylori infection. This case report describes a Helicobacter pylori-positive patient with very extensive ulcerated polypoid lesions involving gastric antrum and prepyloric region, diagnosed by histology, pathological analysis and staging procedures as low-grade MALT lymphoma of EI1 stage. The patient received eradication therapy with a one-week course of omeprazole plus amoxicillin plus clarithromycin and was seen at follow-up after 3, 6 and 15 months. At follow-up, Helicobacter pylori eradication appeared to be in resolution of the macroscopic and histological features of the lymphoma, as confirmed by endoscopic, histological and molecular findings. Until now, only a few cases with a large gastric MALT lymphoma has successful treatment of Helicobacter pylori resulted in regression. Although additional follow-up is needed, it would appear that Helicobacter pylori infection cure may be effective also for large low-grade stage EI1 MALT lymphoma.