88-year-old Amaradeva, born W D Albert Perera, was rushed to Sri Jayewardenepura Hospital here after suddenly falling ill. He died shortly after, the ColomboPage reported.
The music composer drew inspiration from classical Indian ragas as well as Sri Lanka's own rich traditions of folk music and went on to create a music that is quintessentially Sri Lankan.
His contribution to the development of Sinhala music is considered unmatched.
The musician has been the recipient of several awards including the Philippine Ramon Magsaysay Award (2001), Padma Sri Award (2002) and Sri Lankan President's Award of Kala Keerthi (1986) and Deshamanya Award (1998).
Prime Minister Ranil Wickremesinghe, who is currently touring Hong Kong, described him as a "symbol of Sri Lankan classical music".