Amos Singletary (September 1721 – October 30, 1806) was an American gristmill operator and justice of the peace from Sutton, Massachusetts, who served in both houses of the Massachusetts General Court (state legislature). An Anti-Federalist, he voted against the U.S. Constitution as a delegate to the Massachusetts Ratifying Convention. He was angered by perceived Federalist arrogance surrounding the adoption of the Constitution and thought that it provided too much power to the national government. He supported the American Revolution and wanted to limit wealthy Bostonians' sway over state politics.