Karthik Raja (born June 29, 1973) is an Indian composer based in Chennai. He made his debut as a film composer in the Tamil film Pandiyan (1992) and went on to score music for many critically and commercially acclaimed feature films.^[1][2][3]

Karthik Raja is the eldest son of music composer Ilaiyaraaja. His brother Yuvan Shankar Raja and sister Bhavatharini, also Tamil film music directors and playback singers, have worked with him on notable projects. He was schooled at St. Bede's School and Boston Matriculation higher secondary school in Chennai. On 8 June 2000, Karthik Raja married Raja Rajeswari at Tirupati, Andhra Pradesh, India.

Born to a family of musicians, Raja had exposure to various kinds of music from a very early age. He had his formal training in Western classical music from the Trinity School of Music, mainly in piano (affiliated with Jacob John). He also had training in Carnatic music from T. V. Gopalakrishnan and Malayalam composer, V. Dakshinamoorthy.^[4]

As a child, Raja often used to accompany his father to the recording studios. At the age of 13, Karthik Raja played the keyboard for the song Kannukkum from the Tamil movie Ninaikka Therinda Maname (1987). Many such outings followed including playing keyboard for the soundtrack of the movie Nayakan. Karthik also arranged many recordings for his father and composed his first song "Pandianin Rajiyathil" for the movie Pandiyan (1992) and "Ninaikindra" for the movie Athma (1993). Around this time, he also composed some background scores for the TV series Bible.

Raja debuted as a fully-fledged composer in 1996 through the Tamil movie Alexander, soon followed by Manikkam. Then came many chart-busters that included Ullaasam, Naam Iruvar Nammaku Iruvar, Kadhala Kadhala and Dumm Dumm Dumm among others. He also debuted in Hindi films with Grahan which won him the R.D. Burman award for the best new talent.

• 1998: Filmfare RD Burman Award for New Music Talent – Grahan
• 2001: Cinema Express Award for Best Music Director – Dumm Dumm Dumm