Om Prakash Rawat took charge as the chief election commissioner on Tuesday. The Ministry of Law and Justice had confirmed his appointment on Sunday.
Rawat was an election commissioner before taking over from Achal Kumar Joti, who headed the Election Commission since July 2017 and retired on Monday.
The 64-year-old was an officer of the 1977 batch of the Indian Administrative Services from Madhya Pradesh.
Former Finance Secretary Ashok Lavasa was appointed an election commissioner to replace Rawat.
The Indian Constitution stipulates that the chief election commissioner or an election commissioner can have a tenure of six years or hold office till the age of 65 years, whichever is earlier. Rawat is expected to head the polling monitor till December 2018.
During his tenure, the Election Commission will oversee the Assembly elections in Madhya Pradesh, Rajasthan, Karnataka and Chhattisgarh, among others.