Chronic gastritis are inflammatory diseases of the gastric mucosa whose diagnosis depends on pathological examination. They are frequent and cover a significant part of the daily activity of pathologists. Their origin is often infectious, particularly by Helicobacter Pylori. Several classifications of chronic gastritis were proposed but in order to achieve standardization in the drafting of pathological reports of gastric biopsies, pathologists currently following the recommendations of the revisted Sydney System. OLGA (Operative Link for Gastritis Assessment) and OLGIM (Operative Link for Gastritis Intestinal metaplasia Assessment) stages are increasingly used since they allow the clinicians to select patients with « high risk » chronic gastritis, which require special monitoring. The aim of this paper was to perform a review of the different classifications of chronic gastritis currently available to pathologists.