Paranavithana served as the Director General of the Sri Lanka Broadcasting Corporation, Director Editorial of the Associated Newspapers of Ceylon Ltd. and the Chief Executive Officer of the Sri Lanka Rupavahini Corporation. He also served as Consular General of Sri Lanka in Canada.

A product of Lellopitiya Dipitigala Maha Vidyalaya and St. Aloysius Vidyalaya, Ratnapura, Paranavithana obtained his Bachelor of Arts with hounours from the Colombo University and Master of Arts Degree in International Politics from Bradford University, England.

He served as a visiting lecturer on theory and practical aspects of Journalism at both the Colombo and Kelaniya Universities.

He authored Sivveni Anduwe Deshapalanaya (Politics of the Fourth Government).