"3" was an unsuccessful directorial debut of Dhanush's wife, Aishwarya Rajinikanth, while "Raanjhanaa" marks his debut in Bollywood.
"I don't want these two films to be compared because they bear no similarity except for a few scenes in school uniform. Both films have different storylines and are quite different from each other in so many ways," Dhanush told.
Aishwarya's "3" tracks the love story of two students from class 12 to the stage when they tie the knot to become a couple, whereas "Raanjhanaa" focuses on the relationship between a Muslim girl and a Hindu boy.
Although "3" was a box office dud, the song "Kolaveri Di" from the film made Dhanush a global name.
Directed by Anand L. Rai, "Raanjhanaa", which is releasing Friday, is produced by Eros International. It also features Sonam Kapoor, Abhay Deol and Swara Bhaskar in important roles.