Speaking on Swiss television Depardieu, who has worked with some of France’s best known directors including François Truffaut, Alain Resnais, Maurice Pialat and Claude Berri, said he wanted the role because he does not like the man known as DSK.
"He's not lovable. I think he's a bit like all the French, a bit arrogant. I don't much like the French in any case," he said. "He's very French: arrogant, smug. He's playable."
Strauss-Kahn had been the favourite to win next month's French presidential election until May last year, when the former Socialist minister was arrested in New York and accused of sexually assaulting a hotel maid.
Asked about the "impulses" that drive Strauss-Khan's behaviour, Depardieu said he was not disgusted by these, but by his general attitude.
"It's the way he walks, with one hand in his pocket. We can all have filthy thoughts, and it's well known that these guys with huge power, money, the IMF or top judicial officials can be like that," he said.
Depardieu said he would not try to inhabit the role of Strauss-Kahn too deeply, as he had "never been much moved by people who have no dignity."
The actor is a strong supporter of right-wing President Nicolas Sarkozy, who is standing for re-election next month and would probably have faced a tough challenge from 62-year-old Strauss-Kahn if the Socialist had not been arrested.