After Nasim Zaidi retired as Chief Election Commissioner in July, there was a vacancy in the poll panel.
While Achal Kumar Joti is the CEC, Om Prakash Rawat is the other Election Commissioner.
Mr Arora's appointment will be with effect from the day he assumes charge, the law ministry notification said.
Mr Arora (61) had been the Information and Broadcasting Secretary, and Secretary in the Ministry of Skill Development and Entrepreneurship.
He also served as Joint Secretary in the Ministry of Civil Aviation during 1999-2002 and CMD, Indian Airlines for five years (two years as additional charge and three years as full charge).
In Rajasthan, besides district postings in Dholpur, Alwar, Nagaur and Jodhpur, he was Secretary to the Chief Minister during 1993-1998 and Principal Secretary to CM (2005- 2008) and handled Information and Public Relations (IPR), Industries and Investment Departments.