Andrew Adonis, Baron Adonis, PC (born Andreas Adonis; 22 February 1963) is a British Labour Party politician and journalist who served in HM Government for five years in the Blair ministry and the Brown ministry.

He served as Secretary of State for Transport from 2009 to 2010, and as Chairman of the National Infrastructure Commission from 2015 to 2017. He was Chair of the European Movement, from March 2021 until December 2022 having previously served as Vice-Chairman from 2019 to 2021. He is currently a columnist for The New European.

Adonis began his career as an academic at the University of Oxford, before becoming a journalist at the Financial Times and later The Observer. Adonis was appointed by Prime Minister Tony Blair to be an advisor at the Number 10 Policy Unit, specialising in constitutional and educational policy, in 1998. He was later promoted to become the Head of the Policy Unit from 2001 until being created a life peer in 2005, when he was appointed Minister of State for Education in HM Government. He remained in that role when Gordon Brown became Prime Minister in 2007, before becoming Minister of State for Transport in 2008. In 2009, he was promoted to the Cabinet as Transport Secretary, a position he held until 2010.

Adonis has worked for a number of think tanks, is a board member of Policy Network and is the author or co-author of several books, including several studies of the British class system, the rise and fall of the Community Charge, and the Victorian House of Lords. He has also co-edited a collection of essays on Roy Jenkins. Like Jenkins, Adonis speaks with rhotacism. His latest book, Ernest Bevin: Labour's Churchill, is a biography of the Labour politician Ernest Bevin whom, alongside Tony Blair, Adonis regards as a source of inspiration for the modern Labour Party.

Adonis is a strong supporter and advocate of the European Union (EU) and a vocal opponent of Brexit. Following the 2016 United Kingdom European Union membership referendum, he became a key campaigner against the result of the referendum on British departure from the EU, supporting the People's Vote.

Adonis's Greek Cypriot father, Nikos, emigrated from Cyprus as a teenager, becoming a waiter in London, where he met Adonis's English mother. His mother left the family when he was three, and she has had no communication with him since. Shortly thereafter Adonis and his sister were placed in care, because their father was working long hours and was not able to cope with sole parental responsibilities. Adonis lived in a council children's home until the age of 11, when he was awarded a local education authority grant to attend Kingham Hill School, a boarding school in Oxfordshire.

Adonis studied at Keble College, Oxford, where he graduated with a first-class Bachelor of Arts degree in Modern History in 1984. He pursued further studies at Oxford and undertook a Doctor of Philosophy (DPhil) degree at Christ Church, which he completed in 1988 with a thesis entitled The political role of the British peerage in the Third Reform Act system, c. 1885–1914. He was then elected a fellow in history and politics at Nuffield College.

From 1991 to 1996, Adonis was an education and industry correspondent at the Financial Times, eventually becoming their public policy editor. In 1996, he moved to The Observer to work as a political columnist, leader writer and editor.