Ncube takes over from former NewsDay deputy news editor Loughty Dube and will be at the helm of the advocacy organisation for the next five years.
The former deputy chairman was elected unopposed at Misa congress held at a local hotel.
He will be deputised by Kumbira Mafunda of the Zimbabwe Lawyers for Human Rights.
Kelvin Jakachira, the political editor of NewsDay and Lifaqane Nare who is employed by the Zimbabwe Union of Journalists in Bulawayo came in as committee members.
Misa director Nhlanhla Ngwenya said the outcome of the congress had ensured leadership renewal that must be emulated by other organisations.