Polanski and Tarantino were among this year's Cesar recipients Roman Polanski has been named best director at the Cesar awards for his political thriller The Ghost Writer. The film, released as The Ghost in the UK, won three additional prizes for its screenplay, music and editing.
But Polanski missed out on the best film prize, which went instead to the French religious drama Of Gods and Men.
US director Quentin Tarantino received an honorary Cesar at the Paris event, where Facebook drama The Social Network was crowned best foreign film.
Of Gods and Men, inspired by the murder of seven French monks in Algeria in 1996, had led the field ahead of the ceremony with 11 nominations.
Apart from its best film award, though, it only received two other prizes - one for supporting actor Michel Lonsdale and another for its cinematography.
The best actor prize went to Eric Elmosnino for his portrayal of French singer Serge Gainsbourg in a biopic named after him.
His compatriot Sara Forestier was named best actress for The Names of Love, about an activist who converts political opponents to her cause by sleeping with them.
Tarantino was presented his award by Diane Kruger and Christoph Waltz, two of the stars of his 2009 war movie Inglourious Basterds.
Two-time Oscar winner Jodie Foster introduced the event, with French comedian Antoine de Caunes serving as master of ceremonies.