| Honorific-Prefix: | The Hon. |
| Edward Mortimer Macdonald | |
| Smallimage: | Edward Mortimer Macdonald.jpg |
| Constituency Mp: | Antigonish—Guysborough |
| Parliament: | Canadian |
| Predecessor: | Colin Francis McIsaac |
| Successor: | John Carey Douglas |
| Term Start: | 1925 |
| Term End: | 1926 |
| Constituency Mp2: | Pictou |
| Parliament2: | Canadian |
| Predecessor2: | Adam Carr Bell |
| Successor2: | Alexander McGregor |
| Term Start2: | 1904 |
| Term End2: | 1925 |
| Office3: | Member of the Nova Scotia House of Assembly for Pictou |
| Term Start3: | 1897 |
| Term End3: | 1904 |
| Birth Date: | 16 August 1865 |
| Birth Place: | Pictou, Nova Scotia |
| Party: | Liberal |
| Cabinet: | Minister Without Portfolio (1923) Minister of National Defence (1923-1926) |
Edward Mortimer Macdonald, (August 16, 1865 - May 25, 1940) was a Canadian politician.
Born in Pictou, Nova Scotia, the son of John D. and Mary Isabel Macdonald, Macdonald was educated at the Pictou Academy and Dalhousie College where he received a Bachelor of Law in 1887. He was admitted to the Nova Scotia bar in 1887 and the Bar of Quebec in 1918. He was created a King's Counsel in 1904.
He first ran for House of Commons of Canada in the riding of Pictou in the 1896 federal election. Defeated, he lost again in 1900. From 1897 to 1904, he was the Nova Scotia Liberal member of the Nova Scotia House of Assembly for the electoral district of Pictou.
He was elected in the 1904 federal election. A Liberal, he was re-elected in 1908 and 1911. He did not run in 1917, but was elected again in 1921. In April 1923, he was appointed Minister without Portfolio and Minister of National Defence (Acting). From August 1923 to 1926, he was the Minister of National Defence.