Odette Sansom (April 28, 1912 - March 13, 1995) was an Allied heroine of World War II.

Odette Marie Celine Brailly was born in Amiens in the Somme département of France. She married the English subject Roy Sansom in 1931, moving with him to England. When the War Office requested all French-born residents of London to supply them with photographs of their home towns, Odette volunteered her family album which contained many useful depictions of the Channel coast. She was asked to train under Colonel Maurice Buckmaster of the Special Operations Executive and return to France to work with the French underground in Nazi-occupied France. She left her three daughters in the care of her husband.

She made a landing near Cannes in 1942, where she made contact with her supervisor, Peter Churchill. Using the code name Lise, she brought him funds and acted as his radio operator.

Churchill's operation in France was betrayed by a double agent, and Odette and Churchill were imprisoned. Under torture by the Gestapo at Fresnes prison in Paris, Odette stuck to her cover story that Churchill was the nephew of Prime Minister Winston Churchill, and that she was Peter's wife. The hope was that in this way their treatment would be mitigated.

Odette was condemned to death in June 1943 and sent to Ravensbrück Concentration Camp. She survived the war and testified against the prison guards at a 1946 war crimes trial.

Odette's husband had died during her imprisonment and she married Peter Churchill in 1947. They were divorced in 1956.

Her third husband was Geoffrey Hallowes.

Odette was appointed an MBE and was awarded the George Cross.

Works dealing with her story

• Odette, a movie starring Anna Neagle
• Odette: The Story of a British Spy - Jerrard Tickell