Taib received his appointment as governor of the eastern state from the Malaysian King on Friday, a day before his resignation took effect as state minister.
Taib, 77, took his oath of office as governor before the state assembly, which he ruled since 1981 when he first became the chief minister.
While the role of governor is ceremonial, similar to the sultans in other Malaysian states, the position allow Taibs to continue to exert influence in Sarawak's state affairs.
Taib is a pillar for the ruling National Front Coalition. Without the 25 seats that his party and allies won in last year's parliamentary elections, the government of Prime Minister Najib Razak would have lost control of parliament to the opposition coalition.
Taib has named his brother-in-law Adenan Satem as his replacement, another indication that he will retain influence in Sarawak politics.
International environmental groups accused Taib of raping the virgin forests of northern Borneo to enrich his family and cronies.
Activist groups accused him of rigging government projects, such as construction of roads and dams, to favour relatives.
Taib has been under investigation by the country's anti-corruption agency for alleged accumulation of illegal wealth.