Governor E S L Narasimhan administered the oath of office and secrecy to Chandrababu at 7:27 pm, the auspicious "muhurtam" set for the occasion.
Several Union ministers, chief ministers of various states and senior leaders of the Bharatiya Janata Party attended the swearing-in ceremony.
Naidu took oath in the name of God in Telugu amidst thunderous cheers by party workers.
19 cabinet ministers, including three women, were also sworn in on the occasion.
Chandrababu paid obeisance to the statue of Telugu Talli (reverential mother of Telugus) on the dais before taking oath.
Braving the blistering heat, lakhs of people attended the unprecedented grand ceremony on a sprawling 70-acre open site opposite Acharya Nagarjuna University.
Union Ministers Rajnath Singh, M Venkaiah Naidu, Ananth Kumar, Kalraj Mishra, Prakash Javadekar, Nirmala Sitharaman attended the function.
Chief Ministers Parkash Singh Badal of Punjab, Manohar Parikar of Goa, Vasundhara Raje Scindia of Rajasthan, Raman Singh of Chhattisgarh, T R Zeling of Nagaland were also present along with senior BJP leaders L K Advani, Murli Manohar Joshi and several others.
Deputy Chairman of Rajya Sabha P J Kurien and Punjab Deputy Chief Minister Sukhbir Singh Badal were also present.
Bollywood actor Vivek Oberoi and Telugu film stars Pawan Kalyan, NTR Junior and Kalyan Ram also attended the ceremony.
Art of Living guru Sri Sri Ravi Shankar, badminton star Pullela Gopichand, top industrialists like G Mallikarjuna Rao of GMR Group and a host of other VIPs attended the ceremony.
Chandrababu's wife Bhuvaneswari, son Lokesh, daughter-in-law Brahmani and other relatives were also present.
Image: Video grab showing N Chandrababu Naidu taking oath as the first CM of new Andhra Pradesh
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