Kaadhal Kondein (transl. I Fell In Love) is a 2003 Indian Tamil-language romantic psychological thriller film written and directed by Selvaraghavan, credited as his directorial debut. The film stars his brother Dhanush and newcomers Sonia Agarwal and Sudeep Sarangi, while Nagesh and Daniel Balaji play supporting roles. The film, which has music scored by Yuvan Shankar Raja and cinematography handled by Arvind Krishna, was released on 4 July 2003, becoming a critical and commercial success upon release. The film is considered a major breakthrough for Dhanush as it catapulted him into the league of lead actors in the Tamil film industry.

Kaadhal Kondein was remade in Telugu as Nenu (2004), in Bangladeshi as Onno Manush (2004), in Kannada as Ravana (2009), and in Bengali as Amanush (2010).