Arunachalam is a 1997 Indian Tamil-language masala film directed by Sundar C. and written by Crazy Mohan. The film stars Rajinikanth in dual roles, Soundarya and Rambha, with Jaishankar, Ravichandran and Visu in supporting roles. The soundtrack and background score for the film was composed by Deva, while U. K. Senthil Kumar handled the cinematography. The film is loosely based on the 1902 novel Brewster's Millions by George Barr McCutcheon.

The film was released on 10 April 1997 and became a box office success. It won three Tamil Nadu State Film Awards, including Best Film.