He completed his higher education at Tri-Chandra College In 1991, he was elected to the House of Representatives and served as the Minister of Home Affairs in the cabinet led by Girija Prasad Koirala.

[5] Deuba was sworn in as prime minister for a fourth stint in June 2017, as per an agreement to form a rotational government by Congress and the CPN (Maoist Centre).

He came into controversy for having 52 cabinet members in his eighteen month long tenure a move that was criticized by party president Girija Prasad Koirala.

[16][17] Deuba's administration frequently solicited the advice of the opposition in major domestic and foreign policy issues.

His cabinet signed the Mahakali treaty with India, which had been initiated by the previous CPN (UML) government, introduced a system of voter ID and ended dual ownership of land through consensus in the parliament.

[19] Following a breakdown in negotiations, the Maoists resumed their attacks on the government and a state of emergency was declared for six months in February 2002 after a parliamentary vote.

[12][20] The Deuba government failed to hold new elections and asked for fourteen more months citing the growing Maoist insurgency.

Removing an elected prime minister was seen as a autocratic move from the king and was followed by wide spread protests.

[21] Deuba's move to extend the state of emergency and dissolving the House of Representatives was severely criticized by party chairman Girija Prasad Koirala.

After Deuba was expelled from the Nepali Congress, his faction of the party called a general convention that deposed Koirala .

[22] He remained as prime minister until 1 February 2005, when the king seized executive power and placed leading politicians including Deuba under house arrest.

Deuba was the candidate for Nepali Congress for prime minister but lost to CPN (Maoist) leader Pushpa Kamala Dahal, 464-113.

[15] Deuba also unsuccessfully challenged acting president Sushil Koirala at the party's 12th general convention in September 2010.

[18][28] In August 2016, the party agreed on a deal with CPN (Maoist Centre) to run the government for nine months each until the next election.

President Bidhya Devi Bhandari denied this claim and reappointed Oli as prime minister who requested that the House of Representatives be dissolved and called for new elections.

[32][33][34] This was met by a legal challenge in the Supreme Court which ruled in favor of restoring the lower house and appointing Deuba as prime minister in July 2021.

[37][38] At the party's 14th general convention in December 2021, he faced a challenge from Shekhar Koirala, Prakash Man Singh, Bimalendra Nidhi and Kalyan Gurung.

Deuba was re-elected as president defeating Shekhar Koirala with 60% of the vote after Singh and Nidhi supported him in the second round.