It's hard to say which painting is the most stolen, but there's a strong possibility it's a Rembrandt. According to the Guinness World Records, the Dutch artist's “Jacob de Gheyn III” has been stolen at least four times since 1966. It is estimated to be worth $10 million, but a recent auction for it brought in a record-breaking £7 million. The artwork has been found under graveyard benches and on the back of bicycles. The Russian-French painter Marc Chagall's “Othello and Desdemona” has been stolen seven times since 1988.
The Mona Lisa is another famous work that has been stolen more than once. It has been blown up by a bomb in Austria, but was eventually saved by commando agents. Despite its great price, the Mona Lisa has suffered a tough time and is still missing one of her 12 panels. Safe keepers are now increasingly wary of a potential threat to the masterpiece, and have installed large security doors that enable them to easily evacuate panels in case of an emergency.