Dan Brown's tale of intrigue, which has sold three million copies in Britain, was the book most often selected by MPs as they headed for their Greek beaches or Tuscan villas.
The latest instalment of the Harry Potter saga and Louis de Bernieres' Birds Without Wings, an epic love story set in Turkey, were also popular selections.
A survey by CommunicateResearch discovered that Conservatives opted for the critically acclaimed biography of William Pitt the Younger by their former leader, William Hague, while Labour MPs packed Jung Chang's account of Chairman Mao's life in their suitcases.
Both were also taken on holiday by peers, who also chose the late Roy Jenkins' biography of Winston Churchill and Bill Clinton's autobiography.
One unnamed loyal Blairite MP confessed to taking a biography of the Prime Minister, while Tories chose Edwina Currie's Diaries and John Sergeant's Maggie: Her Fatal Legacy.
Two MPs packed the Bible, while other politicians took work with them by bringing the annual report of the Department for International Development and a guide to the results of the general election.
Theresa May, the shadow Culture Secretary, said her favourite read had been The Kite Runner by Khaled Hosseini, which spans nearly 30 years of Afghanistan's turbulent recent history. She also enjoyed Dodie Smith's I Capture the Castle which she described as "engaging and delightful" .
Peter Kilfoyle, the former defence minister, was among those Labour MPs who chose Mao. He said: "I found it fascinating to read of his small-scale idiosyncracies, as well as his indifference to the suffering of so many millions of people."
The Labour MP Eric Joyce chose Philip Roth's latest novel, The Plot Against America, which he found was a "tour-de-force", along with Saturday by Ian McEwan.
The former Europe minister Denis Macshane selected 1812: Napoleon's Fatal March on Moscow by Adam Zamoyski. It was, he said, a "great example of imperial overreach".
Last week, US President George Bush's eclectic holiday reading list was revealed by the White House, including a history of salt. He also took with him Alexander II: The Last Great Tsar, by Edvard Radzinsky, and The Great Influenza: The Epic Story of the Deadliest Plague in History, by John M Barry.
Yesterday Downing Street was unable to shed any light on what books Tony Blair had taken with him on holiday, while a spokeswoman for John Prescott, who has cut short a break in Majorca, said: "He hasn't had a chance to read any books."
MPs' top reads
1 The Da Vinci Code - Dan Brown
2 William Pitt the Younger -
3 Harry Potter and the Half-Blood Prince -
J K Rowling
4 Mao - Jung Chang
5 Birds Without Wings - Louis de Bernieres
Peers' top reads
1 William Pitt the Younger - William Hague
2 Mao - Jung Chang
3 Churchill - Roy Jenkins
4 My Life - Bill Clinton
5 Who Runs This Place?: The Anatomy of Britain in the 21st Century - Anthony Sampson