Wearing his trademark white panche (lungi) and white shirt, Mr Naidu took oath in Hindi in the name of god.
Prime Minister Narendra Modi, former vice-president Hamid Ansari, Lok Sabha Speaker Sumitra Mahajan, former Prime Minister Manmohan Singh, leader of the opposition in the Rajya Sabha Ghulam Nabi Azad, BJP veteran L K Advani, several union ministers, governors and chief ministers attended the ceremony.
Samajwadi party leader Mulayam Singh Yadav, National Congress Party's Tariq Anwar, Communist Party of India leader D Raja, Trinamool Congress leaders Sudip Bandhopadhyay and Derek O'Brien and AIADMK's O Panneerselvam were also seen.
Delhi Chief Minister Arvind Kejriwal and his Bihar counterpart Nitish Kumar -- who has joined hands with the BJP in his state -- also attended the ceremony at Rashtrapati Bhawan.
Mr Naidu's wife M Usha was also present.
This remarkable career in politics has been more than four decades in the making.
It began in the 1970s when BJP's precursor Jana Sangh was a marginal player with little clout in the south and a young party worker kept himself busy putting up posters of stalwarts such as Atal Bihari Vajpayee and L K Advani.
Mr Naidu has come a long way since those days of political obscurity.
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