John McDonald (February 10, 1787 – September 20, 1860) was a businessman and political figure in Upper Canada and Canada West. He was born in Saratoga, New York in 1787, the son of John McDonald, a Scottish immigrant. He set up in business at Troy, New York but joined his older brother Charles in the timber and grain trade at Gananoque in 1815. They built a large water-powered flour mill on the Gananoque River in 1826. Later that year, Charles died and John became the principal owner of the business. He was named a justice of the peace and postmaster for Gananoque in 1828. In 1831, he married Maria, the daughter of Benajah Mallory. In 1836, he was named a commissioner for improving navigation on the Saint Lawrence River; McDonald became president of the commission in 1838. In 1839, he was