The appointment was made effective on Friday, 27 January.
Ma’u has signed his contract for four-years following his appointment by the Public Service Commission.
He started with the Government of Tonga as Head of the Budget Division of the Ministry of Finance in 1993, before taking the Deputy Secretary post at the Prime Minister’s Office in 1996, a post he held for 16-years.
He was appointed as the first Secretary for the Ministry of Information and Communication in 2010.
Ma'u takes over from Edgar Cocker whose term ended late 2022.