The Memorial Hall is the College's principal memorial to the 749 men who gave their lives in World War I. It was opened by H.R.H. The Duke of Connaught on May 23rd, 1925.

The hall stands to the west of the Court (at the centre of the College) and is linked to the chapel by means of stone steps leading down to the its brick-paved forecourt.

It was designed to have a maximum capacity of about 800 and so today, even with extra chairs placed around the ambulatory, the whole College can only just be squeezed in. Thus, apart from short whole school assemblies at the start and finish of each term, it is more usual for the hall to be used for Lower or Upper School assemblies.

Some musical events, including the Marlborough College Subscription Series, and other entertainment events such as the House Shout and the pupil-led Illumination also take place in the Memorial Hall.