Narasimhan was administered the oath of office by AP High Court Chief Justice A Ramesh Dave at a brief function in the Raj Bhavan at 9.45 am this morning.
Chief Minister K Rosaiah, his Cabinet colleagues, state Chief Secretary S V Prasad and others attended the function.
The Chief Secretary read out the warrant of appointment of Narasimhan following which the High Court Chief Justice administered the oath.
A former Indian Police Service (IPS) officer of the Andhra Pradesh cadre, Narasimhan was sworn-in as the in charge Governor of the state on December 28 following the resignation of Narayan Datt Tiwari after his name figured in a sex scandal.
Last week, President Pratibha Patil appointed Narasimhan as the full-time Governor of Andhra Pradesh, shifting him from neighbouring Chattisgarh.
Accordingly, Narasimhan was administered the oath of office as the regular Governor of the state.
Narasimhan also served as Chief of the Intelligence Bureau earlier. He arrived here late last night and was received at the airport by Chief Minister K Rosaiah.
Sankaranarayanan as Governor of Maharashtra
Earlier, Sankaranarayanan was the Governor of Jharkhand, the swearing-in took place at 10 am at the Raj Bhavan where Acting Chief Justice of Bombay High Court J N Patel administered the oath of office to him.
Outgoing Governor S C Jamir, Chief Minister Ashok Chavan, Deputy Chief Minister Chhagan Bhujbal, members of the state cabinet were among those present on the occasion.
79-year-old Sankaranarayanan brings with him a vast and varied experience in public life and had dominated the political firmament of Kerala for nearly five decades.
Born on October 15, 1932 in Kerala, Sankaranarayanan's initiation into politics started early when he became a member of Students Organization in 1946.
He rose to the position of Kerala Congress president in 1977 after serving as General Secretary and President of the Palghat district unit of the party and also served as the Working Committee Member of the AICC.
Sankaranarayanan was elected to the Kerala Legislative Assembly several times and represented Thrithala, Sreekrishnapuram, Ottappalam and Palghat constituencies. He was also a member of the ministries of K Karunakaran and A K Antony.
M.O.H. Farook as Jharkhand governor
M.O.H. Farook became the seventh governor of Jharkhand Friday, less than a month after Shibu Soren took over as the state's seventh chief minister.
Farook was administered the oath of office and secrecy by Jharkhand High Court Chief Justice Gyan Sudha Mishra at the Raj Bhavan here.
He replaces K. Sankaranarayanan, who has been appointed governor of Maharashtra.
Farook was born at Karaikal in Pondicherry on Sep 6, 1937. He was chief minister of Pondicherry three times and represented it in the Lok Sabha on three occasions. In 2004, he was appointed ambassador to Saudi Arabia.