The 36th Infantry Brigade was an infantry brigade formation of British Army that fought in the First World War, as part of 12th (Eastern) Division, on the Western Front.

The brigade also fought in the Second World War, with the 12th (Eastern) Infantry Division, in France, and later with 78th Infantry Division in Tunisia and Italy.

The 36th Brigade fought throughout the First World War with the 12th (Eastern) Division on the Western Front.

It fought in the Battle of France in May 1940 where it was overrun by the German Army and dispersed and suffered very heavy casualties, due mainly to the division having none of its support units and the infantrymen having had little training.

Reformed in the United Kingdom, it was redesignated 36th Independent Infantry Brigade from 22 June 1940, when the 12th Division was disbanded, until 22 June 1942 when it was assigned to the 78th Battleaxe Infantry Division and served in the North African Campaign, in Operation Husky and the Italian Campaign, in particular the Battle of Monte Cassino and later Gothic Line, followed by the Spring 1945 offensive in Italy.