Speaking at a conference at Santa Croce University in Rome, Monsignor Angelo Amato, the second-ranking official in the doctrinal department, said the best-selling book and the movie contain "offense and calumny" as well as "historical and theological errors," the Italian news agency Ansa said.
"I hope you will all boycott the film," he said.
The book by Dan Brown claims that the Roman Catholic Church has conspired to hide the truth that Jesus and Mary Magdalene married and had children whose descendents are still alive. Brown also attacks a conservative Catholic group favored by Pope John Paul II with one villain being a monk who belongs to Opus Dei.
Amato said that an equivalent fictional attack on Islam would have provoked worldwide outrage among Muslims.