Vice-Admiral Daniel Nicolas Mainguy CMM, CD (2 December 1930–17 August 2010) was a Canadian Forces officer who served as Vice Chief of the Defence Staff.

The son of Vice-Admiral Rollo Mainguy, Mainguy joined the Royal Canadian Navy in 1949, initially in the Reserve and then, from 1950, in the Regular service.

[1] He became Commanding Officer of HMCS Annapolis in 1966, Staff Officer and Operations Officer with Standing Naval Force Atlantic in 1967 and Director of Operational Readiness Maritime in 1970.

[1] He went on to be Director of Strategic Planning in 1973, Chief of Maritime Doctrine and Operations in 1976 and Chief of Staff to the Commander-in-Chief, Western Atlantic in 1979.

[2] Mainguy's personal awards and decorations include the following: