Rangaraj was born in a village near Kovilpatti. While searching for job in Chennai, he decided to join Tamil film industry after being influenced by films directed by K. Balachander. He struck friendship with M. G. Vallabhan who introduced him to Bharathiraja. Rangaraj who went to assist Bharathiraja in various films made his directorial debut with Nenjamellam Nee in 1983. The film became successful and Rangaraj went on to direct successful films like Unnai Naan Sandhithen (1984), Udhaya Geetham (1985) Geethanjali (1985) and Paadu Nilave (1987). However subsequent failures like Dharmam Vellum (1989) and Ellaichami (1992) which he also produced led him in a financial crunch which also led him to leave films completely and directed serials for sometime.
- Nenjamellam Neeye (1983)
- Ponnu Pudichirukku (1984)
- Nilavu Suduvathillai (1984)
- Unnai Naan Santhithaen (1984)
- Udaya Geetham (1985)
- Geethanjali (1985)
- Amutha Gaanam (1985)
- Uyire Unakkaga (1986)
- Manithanin Marupakkam (1986)
- Unakkaagave Vaazhgiren (1986)
- Sathya Jyothi (1986; Kannada)
- Paadu Nilave (1987)
- Ninaive Oru Sangeetham (1987)
- Gramatthu Minnal (1987)
- Dharmam Vellum (1989)
- Sivaranjani (1991)
- Ellaichami (1992)
- "'15 படங்கள் ஹிட்...' - 'உதயகீதம்' கே.ரங்கராஜ் - 15 வருடங்களுக்குப் பிறகு மனம் திறக்கிறார்". Kamadenu.in. Retrieved 3 April 2019.
- Hindu Tamil Thisai (24 April 2018). "Ilayaraja is the reason for Everything! - 'Udhayageetham' Director Rangaraj Interview". YouTube. Retrieved 3 April 2019.
- "Songs Download, Tamil MP3 Songs, Raaga.com Tamil Songs". Raaga.com. Retrieved 3 April 2019.
- "Uyire Unakkaaga (1986) - Uyire Unakkaaga Movie - Uyire Unakkaaga Tamil Movie Cast & Crew, Release Date, Review, Photos, Videos". FilmiBeat.com. Retrieved 3 April 2019.
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