Absalom Willis Robertson (May 27, 1887 – November 1, 1971) was an American politician from Virginia who served in public office for over 50 years. A member of the Democratic Party and an ally of the Byrd Organization led by fellow U.S. Senator Harry F. Byrd, Robertson represented Virginia in the U.S. House of Representatives (1933–1946) and the U.S. Senate (1946–1966), and had earlier served in the Virginia General Assembly. A member of the conservative coalition during his congressional career, Robertson was a vocal opponent of civil rights. Robertson was also the father of televangelist and political commentator Pat Robertson.

Robertson was born in Martinsburg, West Virginia, the son of Franklin Pierce Robertson and Josephine Ragland (née Willis), just two weeks before fellow Virginia Senator Harry F. Byrd was born in the same community. He graduated from the University of Richmond in 1907.

Robertson established a private law practice following graduation, and soon embarked on a political career. He was elected to the Virginia State Senate as a Democrat in 1915 to represent Bedford and Rockbridge counties and Buena Vista, Virginia, in Senate district 22, replacing W. T. Paxton, who had replaced J. Randolph Tucker in 1913. Robertson served from 1916 to 1922, when he resigned and was replaced by Samuel S. Lambeth Jr. in the February 1923 special session. The constituency was renumbered as the 23rd district in advance of the General Assembly's 1924 session. During World War I, Robertson enlisted and served in the United States Army, but was assigned stateside so he could continue that part-time elective office.

Robertson served as Commonwealth Attorney for Rockbridge County, Virginia (an elective office per the Virginia constitution, which prohibited such officials from also serving as legislators or judges during their terms) from 1922 to 1928.

In 1932, Robertson was elected from Virginia's 7th congressional district to the U.S. House of Representatives, and was reelected six times. In 1946, he won a special election for the right to complete the final two years of Senator Carter Glass's term and took office on the day after the election. He won the seat in his own right in 1948 and was reelected two more times without serious opposition.

Among his legislation is the Pittman–Robertson Federal Aid in Wildlife Restoration Act which creates the formula for federal sharing of ammunition tax revenues with states to establish wildlife areas. The program is still in effect and remains a primary financing source for wildlife areas.

Robertson was a typical member of the Byrd Organization, though his opinions differed at times and eventually became independent from the machine. He was chairman of the U.S. Senate Committee on Banking, Housing, and Urban Affairs from 1959 to 1966. In 1956, Robertson was one of the 19 senators who signed the Southern Manifesto against the U.S. Supreme Court decision of Brown v. Board of Education of Topeka (1954), which mandated schools' desegregation.

When President Lyndon B. Johnson sent his wife, Lady Bird Johnson, on a train trip through the South to encourage support for the Civil Rights Act of 1964 and the Voting Rights Act of 1965, Robertson was one of four Southern Senators who refused to meet with her on the whistle-stop trip.