Abstract:For a long time, the concept that stress and lifestyle were considered the major causes of gastritis andpeptic ulcer disease prevailed in medical community. Two Australian scientists, unrestricted by the classical medi-cal concept, pioneeringly demonstrated that helicobacter pylori, a new genus, were the real cause for gastritis andpeptic ulcer disease. Then the therapeutic methods for these diseases were changed. Gastritis and peptic ulcerdisease are no longer chronic and relapsing diseases, but diseases that can be cured. In order to praise their contribution,the Noble Assembly at Sweden Royal Karolinska Institute has awarded them the Nobel Prize for Physiology orMedicine for 2005.