Agni Deo Singh is an Indo-Fijian teacher, who has risen through the ranks of the Fiji Teachers Union (FTU) to become its general secretary. He was also elected to the House of Representatives in 2006. Singh was born in rural Macuata in Vanua Levu, the second largest island in the Fiji Archipelago. After teacher training, he taught at Kadavu and Nausori. While teaching at Nausori he completed Diploma in Education, then did a Certificate in Non Formal Education as an external student of the University of the South Pacific. He completed his degree through summer schools.
In 1980, he became the secretary of the Rewa branch of the FTU and in 1984, became the chairman of the branch. In 1987, he became the branch representative to attend national executive meetings and in 1992 became the assistant general secretary. In 1999, following the election of the incumbent, Pratap Chand to Parliament, he became the general secretary of the FTU.
He was elected to Parliament following the general election in May 2006 on the Fiji Labour Party ticket from Macuata East Open Constituency but following the 5 December 2006 military coup, he returned to his post in the trade union.
On 14 April 2007, Singh was re-elected to the post of General Secretrary of the Fiji Teachers Union.