Ilaiyaraaja (Tamil: இளையராஜா, pronounced ɪləjəɹɑːdʒɑː) (born Daniel Rajaiyya on June 2, 1943) is an Indian film composer, singer, lyricist and the first Asian composer to score a symphony for the Royal Philharmonic Orchestra. He is a gold medalist from Trinity College of Music, London, and has composed over 4, 500 songs and provided film scores for more than 900 Indian films in various languages in a career spanning more than 30 years. He is usually referred to by the title Isaignani (literally meaning 'a man with great knowledge in music'), or as "The Maestro". He is based in Chennai, the centre of the Tamil film industry (colloquially known as Kollywood).

Ilaiyaraaja has been a prominent composer of film music in southern Indian cinema since the late 1970s. His work integrated Tamil folk lyricism and introduced broader Western musical sensibilities into the South Indian musical mainstream. He has thrice won the Indian National Film Award for best film scoring. In the 2000s, he composed a range of non-film music, including religious and devotional songs, an oratorio, and world music. He is married to Jeeva, and the couple's two sons (Karthik Raja and Yuvan Shankar Raja) and daughter (Bhavatharini) are film composers and singers.