Coppola told Argentina's Todo Noticias he had lost 15 years' worth of data during a robbery at his house, which is also where his Zoetrope Argentina studio is based, the BBC has reported.
A script for his latest film "Tetro," starring Matt Dillon, was on one of the computers taken along with camera equipment, however, Coppola's publicist said copies of the screenplay were saved elsewhere.
"They stole our computers; they got all our data, many years of work," said Coppola, a five-time Oscar-winning filmmaker best-known for his "Godfather" movies.
He said the backup was just "a little thing but the information is (worth) much time."
"If I could get the backup back, it would save me years (of) all the photographs of my family, all my writing," he added.
"Tetro" is about multi-generational rivalries in an artistic Italian family living in Buenos Aires, the BBC said.