Russell body gastritis is a very rare disease with an uncertain cause. The disease is often misdiagnosed as xanthoma, signet ring cell carcinoma, MALT lymphoma and plasmacytoma. Russell body gastritis is characterized by the polyclonic nature of immunoglobulin and usually tests positive to the kappa and lambda light chains. It is different from a Mott cell tumor, which shows monoclonal nature of immunoglobulin. Until now, few cases have been reported and most were associated with a Helicobacter pylori infection. We encountered a case of Russell body gastritis associated with a Helicobacter pylori infection, which showed complete improvement after eradicating the Helicobacter pylori infection. We report this case with review of the relevant literature. (Korean J Gastrointest Endosc 2007;35:181-185)