Donald Macpherson Baillie (1887 – 1954) was a Scottish theologian, ecumenist, and parish minister.
Raised in the Calvinist tradition, Baillie studied at Edinburgh University and then in Marburg where he was influenced by the theologian Wilhelm Herrmann. After some time as a Church of Scotland parish minister, he wrote Faith in God and its Christian Consummation (1927). This led to his appointment as a professor of divinity at St Mary's College, University of St Andrews, where he spent the remainder of his life.
His only other, and more famous, work was God was in Christ (1948) which explored the paradox of grace, and applied it to incarnational theology.
He was the brother of Scottish theologian John Baillie (1889-1960).