A <i>Helicobacter pylori</i> adhesion inhibitor whereby <i>Helicobacter pylori </i>participating in the onset of digestive ulcer can be eliminated from the stomach; a process for producing the same; and drugs and foods containing the same for preventing or treating diseases relating to <i>Helicobacter pylori</i>. The <i>Helicobacter pylori</i> adhesion inhibitor has an excellent effect of eliminating <i>Helicobacter pylori</i> and a high safety. Therefore, medicinal compositions and foods containing the same are highly useful in preventing or treating the diseases as described above.
