Samuel Blair (1741 – September 1818) was an American Presbyterian minister and the second Chaplain of the United States House of Representatives.

While traveling to Boston, he survived a shipwreck but became ill and lost his possessions including the sermons he had written.

Because of his poor health, and conflict with his church members regarding the Half-Way Covenant, he resigned and was dismissed on October 10, 1769.

He was appointed the second Chaplain of Congress on December 10, 1790, a position he held for two years, until he was replaced by Ashbel Green on November 5, 1792.

Blair was a member of the American Philosophical Society (elected in 1797) and died in Germantown in September 1818.