Aged 61, he had been hospitalised after being unwell for some time.
An old boy of Royal College, Mr. Liyanage began his career as a photographer for the Wijeya Newspapers and is also the screenwriter of several controversial films such as Prasanna Vitanage's 'Ira Madiyama'.
He was also the Unit Still Photographer of the iconic film 'Dadayama', directed by Wasantha Obeysekera.
Joining the BBC World Service in London as a freelancer in the late 1980s, he later became a senior producer at the BBC before being appointed Editor of the Sinhala Service in 1997.
The feature 'Ghostly Voices of the World War One' created by Priyath Liyanage for the BBC World Service, won an international award for Best Radio Feature.
Liyanage retired from the BBC Sinhala service in 2014 after serving as the editor for more than 17 years.