John Mactaggart or McTaggart may refer to:
Sir John McTaggart, 1st Baronet (1789–1867), Scottish Liberal MP in the British Parliament John Mactaggart (writer) (1791–1830), Scottish author and engineer John MacTaggart (1823–1871), early settler of Kilkivan, Queensland J. M. E. McTaggart (John McTaggart Ellis McTaggart, 1866–1925), English idealist metaphysician Sir John Mactaggart, 1st Baronet (1867–1956), Scottish builder John McTaggart (jockey) (1896–1946), American jockey Sir John Mactaggart, 2nd Baronet (1898–1960), Scottish businessman, son of the 1st Baronet; see Mactaggart baronets Sir John Mactaggart, 4th Baronet (born 1951), Scottish businessman and philanthropist, grandson of the above John Auld Mactaggart (born 1993), heir of the above