The Sergeants-at-Arms of the House of Commons of Canada is a senior officer for the legislative body appointed by Governor General-in-Council through letter patent under the Great Seal of Canada.^[1] The Sergeant-at Arms assists the Clerk of the House of Commons as head of parliamentary precinct services, performing certain administrative and ceremonial functions, and maintaining order and security in the parliamentary buildings.^[1]

Ceremonial functions performed by the sergeant-at-arms includes administering the Canadian oath of allegiance to newly elected members of the House of Commons.^[1] Additionally it is the sergeant-at-arms’ responsibility to bring the ceremonial mace into the legislative chambers before the Speaker of the House of Commons enters the chambers.^[1] The sergeant-at-arms occupies a bar in the chambers until proceedings are completed, after which he removes the ceremonial mace from the chambers.^[1]

Ten individuals have been appointed to the position since Canadian Confederation in 1867. All previous appointees previously held positions in the Canadian military or the Royal Canadian Mounted Police;^[1] although there is no requirement that requires appointees to be drawn from these services. The current Sergeant-at-Arms is Pat McDonell, who was formally appointed to the position in July 2019.^[2]