| Honorific-Prefix: | The Honourable |
| Donald McDonald MacKay | |
| Office: | Member of the Legislative Council of Western Australia |
| Constituency: | North Province |
| Term Start: | 27 July 1896 |
| Term End: | 21 May 1902 |
| Predecessor: | Edward Robinson |
| Successor: | Sir Edward Wittenoom |
| Birth Date: | c. 1845 |
| Birth Place: | Isle of Skye, Scotland |
| Death Date: | 30 January 1904 |
| Death Place: | Fremantle, Western Australia, Australia |
Donald McDonald MacKay (c. 1845 – 30 January 1904) was an Australian pastoralist and politician who was a member of the Legislative Council of Western Australia from 1896 to 1902, representing North Province.
MacKay was born in Ben Mohr Estate,[1] Snizort, Isle of Skye, Inverness-shire in 1847, a son of Samuel Nicholson Mackay and Janette Mackay (née McKinnon) (died 23 June 1891),[2] who emigrated with their family to South Australia in 1855, settling in Naracoorte. MacKay left for Western Australia in 1869, and went to the Pilbara, where he developed a pastoral lease on the Maitland River. With his brother, Roderick MacKay, he later developed Mundabullangana Station on the Yule River. In 1892, after a drought, MacKay sold his property in the North-West and moved to Fremantle. He was elected to the Legislative Council for the North Province at the 1896 elections,[3] replacing Edward Robinson, and served a single six-year term before retiring. MacKay died in Fremantle in January 1904.
MacKay married (Emily) Charlotte Vincent on 21 February 1893 at Scots Church, Fremantle,[4] with whom he had three children.[5]
The author Catherine Edith Macauley Martin was his youngest sister, and it may be noted that the subject of this article, Donald McDonald MacKay, had a brother (third son of Samuel) Donald Mackay (1832 – 24 December 1901),[6] sheep grazier of Mundabullangana,[7] Yule and Benmore stations.[6]