Elizabeth Lynne Cheney (/ˈtʃeɪni/; born July 28, 1966) is an American attorney and former politician who was the U.S. representative for Wyoming's at-large congressional district from 2017 to 2023, and served as chair of the House Republican Conference from 2019 to 2021. A member of the Republican Party, she is known for her vocal opposition to Donald Trump.

Cheney is the elder daughter of former vice president Dick Cheney and second lady Lynne Cheney. She held several positions in the U.S. State Department during the George W. Bush administration. She promoted regime change in Iran while chairing the Iran Syria Policy and Operations Group with Elliott Abrams. In 2009, Cheney and Bill Kristol founded Keep America Safe, a nonprofit organization concerned with national security issues that supported the Bush–Cheney administration's positions. In 2014 she was briefly a candidate for the U.S. Senate in Wyoming, challenging incumbent Mike Enzi before withdrawing. She was elected to the House of Representatives in 2016, holding the same seat her father had held from 1979 to 1989.

Regarded as a leading ideological neoconservative in the Bush–Cheney tradition as well as representative of the Republican establishment, Cheney is known for her pro-business stances and hawkish foreign policy views. She was critical of the foreign policy of the first Donald Trump administration while consistently voting in favor of Trump's overall agenda.

Cheney supported the second impeachment of Donald Trump following the 2021 storming of the U.S. Capitol. Her impeachment vote and criticism of Donald Trump led to her eventual removal from Republican leadership in May 2021. In July 2021, Speaker Nancy Pelosi appointed Cheney to the House Select Committee on the January 6 Attack. Two months later, she was made vice chair of the committee. Her role on the committee resulted in the Wyoming Republican Party revoking Cheney's membership in November 2021 as well as censure from the Republican National Committee in February 2022.

In 2022, Cheney lost renomination in Wyoming's Republican primary to Trump-endorsed Harriet Hageman in a landslide, garnering just 28.9% of the vote. Cheney has said that she intends to be "the leader, one of the leaders, in a fight to help to restore" the Republican Party. She later endorsed and campaigned for Kamala Harris's unsuccessful run in the 2024 presidential election. In 2025 she was awarded the Presidential Citizens Medal and pardoned from potential future prosecution by President Joe Biden. As of March 2023, she is a professor of practice at the University of Virginia Center for Politics.

Elizabeth Lynne Cheney was born on July 28, 1966, in Madison, Wisconsin. She is the elder of two daughters of former vice president Dick Cheney and former second lady Lynne Cheney (née Vincent). At the time of her birth, her parents were studying at the University of Wisconsin–Madison. Her younger sister, Mary Cheney, was also born in Madison. Cheney attended part of sixth and seventh grade in Casper, Wyoming, while her father campaigned for Congress. The family divided its time between Casper and Washington, D.C., in the 1970s through the 1980s, following her father's election to Congress. In 1984 Cheney graduated from McLean High School in suburban Washington, D.C., where she was a cheerleader. In 1988, Cheney received her political science BA in from Colorado College, her mother's alma mater, where she wrote a senior thesis entitled "The Evolution of Presidential War Powers." She received her JD degree from the University of Chicago Law School in 1996. While there, she also took courses in Middle Eastern history at the Oriental Institute.

Before attending law school, Cheney worked for the State Department for five years and the United States Agency for International Development between 1989 and 1993. After 1993, she took a job at Armitage Associates LLP, the consulting firm founded by Richard Armitage, then a former Defense Department official and later the deputy secretary of state.

After graduation from law school, Cheney practiced law at the law firm of White & Case and as an international law attorney and consultant at the International Finance Corporation, a member of the World Bank Group. She was also special assistant to the deputy secretary of state for assistance to the former Soviet Union, and a USAID officer in U.S. embassies in Budapest and Warsaw.