Joffo was born in Paris in the 18th arrondissement. He left school at 14 with a certificat d'études (a former school leaving certificate, taken at the end of primary education) in his pocket and joined his brothers in the family's barber shop.
A Bag of Marbles
His memoirs Un sac de billes (A Bag of Marbles) were published and written in a novel fashion and tell the account of Joffo as a young Jewish boy during the Holocaust. When Joseph Joffo was ten years old, his father gave him and his brother five thousand francs each and instructions to flee Nazi-occupied Paris and, by foot, train and bus, join their brothers Henri and Albert in Menton on the Mediterranean coast, where they'd be safe. The book "A Bag of Marbles" tells of this journey.
Joffo and his twelve-year-old brother, Maurice, travel all around France by themselves. They are attempting to escape from the grasp of Hitler and his S.S. men as they infiltrate France. They travel through northern France to the de-militiarised zone in the South. The boys then spend four blissfully safe months in Menton with their brothers, Henri and Albert, before having to leave the town for Nice where their parents are waiting.
Joffo returns to Paris shortly after its liberation is announced in an over-crowded train. Maurice does also, although in his typical style he also takes enough cheese to make a very large profit on. They are both re-united with their family in the coiffeur - although sadly not their father, who perished in a concentration camp before the end of the war.
Joffo has also written the book Anna et son orchestre (Anna and Her Orchestra), which tells the story of Joseph's mother, from the time she is 11 years old to the time she meets Joseph Joffo's father in Paris.
His novel Baby-foot, published in 1977, follows on from Un sac de billes and describes his life in Paris following WWII and his discovery of American values.
La Vieille dame de Djerba, published in 1984, was written after Joffo met a woman called Liza at a synagogue in Djerba, an island off the coast of Tunisia. He was amazed to discover, after assuming she was a beggar and offering her money, that she knew the name of his mother and grandmother.
On 10 December 1975, Un sac de billes premiered in France as a motion picture. The film was also released internationally entitled A Bag of Marbles. They are currently filming 'Un Sac de Billes' for release later in 2015. It has caused quite a frenzy among locals in Nice, where the production team hung a Nazi flag from the Palais des Rois Sardes. 
- Joffo, Joseph (2000). A Bag of Marbles. University of Chicago Press. ISBN 978-0-226-40069-3.