Pierce Butler (July 11, 1744 – February 15, 1822) was a soldier, planter, and statesman, recognized as one of United States' Founding Fathers. He represented South Carolina in the Continental Congress, the 1787 Constitutional Convention, and the U.S. Senate.

One of the largest slaveholders in the United States, Butler defended American slavery for both political and personal motives, though he had private misgivings about the institution, and particularly about the African slave trade. He introduced the Fugitive Slave Clause of the U.S. Constitution during the convention, and supported other measures to benefit slaveholders, including counting the full slave population in state totals for the purposes of Congressional apportionment. The compromise measure provided for counting three-fifths of the slave population in state totals, which led to Southern states having disproportionate power.

Butler was born to an aristocratic Irish family, a son of Sir Richard Butler, 5th Baronet of Cloughgrenan , near the village of Tinryland, County Carlow, in Ireland. As the third son, he could inherit neither the title nor land, so his father purchased a commission for him in the British Army. He went to South Carolina in 1767 as a major with the Twenty-Ninth Regiment of Foot. As late as 1772, he was a ranking officer in British units charged with suppressing the growing colonial resistance to Parliament.