Director Quentin Tarantino is keen to secure the Inception star for his new project, which is inspired by Sergio Corbucci's 1966 spaghetti Western Django.
DiCaprio would play the movie's villainous plantation owner Calvin Candie, Variety reports.
The actor's representatives have not yet commented on the speculation.
Tarantino also reportedly wants Will Smith to play the lead role of Django. The part is said to have been written with the Men in Black star in mind.
However, speculation arose earlier this week that Thor actor Idris Elba is also in consideration for the part.
Leaked pages from the film's script have revealed that Django is an escaped slave. He teams up with a German bounty hunter to free his wife from slavery and get revenge on his former master.
DiCaprio will next be seen on screen in historical biopic J. Edgar, which is due for release in US cinemas on December 14.
He has also been cast as Jay Gatsby in Baz Luhrmann's adaptation of F. Scott Fitzgerald's classic novel The Great Gatsby.