Sir Donald Norman McKay KCMG (28 November 1908 – 30 March 1988) was a New Zealand politician of the National Party.

In early 1954 the 77 year-old MP for Marsden Alfred Murdoch was challenged for the National nomination by William Rodney Lewin Vallance, the deputy mayor of Whangarei.

Vallance won a postal ballot of members, an outcome which split the Marsden National Party membership into two opposing factions.

[6] Following National's victory in 1960, Deputy Prime Minister Jack Marshall was unable to convince Keith Holyoake to include McKay in the cabinet.

Holyoake thought that McKay had not sufficiently proved himself in the house, but later appointed him following a midterm vacancy based on Marshall's endorsement.