Kapuge was born on August 7, 1945 either in the village of Miriswatte in the Galle District or in the tiny village of Thanabaddegama in Elpitiya. He was the second of eight children. He went to school until grade five at Karandeniya Central and later at Dharmasoka College in Ambalangoda, where he initially studied science before switching to music. In 1963, he left Haywood college of music, where he was studying at that time, to follow a degree course in India
. In the late 1960s, Kapuge joined the Sri Lanka
Kapuge released his first song `Daesa Nilupul Thema` in 1973, which became an instant hit. After, Kapuge was selected as a Grade `A` vocalist by the Radio Ceylon
and started his three decade long music career. The First Stage Drama for which he provided back-ground music was `Thuranga Sanniya` by Sugathapala De Silva. Since then he provided background music for the highly popular musical `Tharawo Igilethi` by Lucien Bulathsinhala and several other popular dramas. His first movie back-ground music gig was for the Stanley Perera`s `Sandha.` He married Prema Withanage in 1978. In 1980, Kapuge released his first music cassette titled `Dhampatin Laa Sandha` with Malini Bulathsinhala. He released several cassettes during the 1980s, most of them selling very well. Among them were, Seethala Sandha Eliye (1981), Unmadha Sithuwam (1983
), Mawathe Giithaya (1985), and Piya Satahan (1990).
Kapuge staged a one-man musical show titled `Kampana` during the 1990s and also released a cassette and CD with the same title. He died on April 3, 2003, at the age of 58, at the Colombo National Hospital, after sustaining critical injuries in a fall from the shuttle bus at Bandaranaike International Airport. He had been returning from a show in Dubai, United Arab Emirates. There was a delay in taking him to the hospital  which lead to a national inquiry.