Sardar Saleem Haider took oath as Punjab governor, the 24NewsHD TV channel reports.
The Lahore High Court chief justice administered the oath to him.
Pakistan People's Party Chairperson Bilawal Bhutto and Punjab Chief Minister Maryam Nawaz also attended the oath-taking ceremony.
The PPP chairman nominated him for the key position earlier this month and the nominee got the approval of President Asif Ali Zardari.
According to the President’s Office, the head of the state accorded his approval based on Prime Minister Shehbaz Sharif’s advice in accordance with Article 101 (1) of the Constitution.
Sardar Saleem belongs to Punjab’s Attock district. He served as a former federal minister and prime minister’s aide for overseas Pakistanis in the previous tenure of the Pakistan Muslim League-Nawaz (PML-N) government.