He is the senior-most Sri Lankan judge and has served in the island's courts for the past 37 years.
De Silva started his career as a government solicitor and has served as the Deputy Solicitor General, and a judge of the High Court and of the Appeal Court.
He also served as a member of the panel of judges attached to United Nations War Crimes Commission.
De Silva's appointment came the day after the retirement of Sarath N Silva as chief justice and at a time when Sri Lanka is under pressure from Western powers to probe alleged war crimes in the war against the Tamil Tigers.