In 2004, Barnaby was elected to the Senate in Queensland. In 2009, he became The Nationals Leader in The Senate and Shadow Minister for Regional Development, Local Government and Water.

Barnaby was elected in 2013 as the Member for New England. In 2013 he was appointed Federal Minister for Agriculture and Deputy Leader of The Nationals with Water Resources later being added. In 2016, he was elected unopposed as Leader of The Nationals and was sworn in as Deputy Prime Minister. Following the High Court of Australia ruling in 2017 regarding his dual citizenship matter, Barnaby again stood as The Nationals’ candidate for New England at the by-election, and was re-elected in 2017. In the subsequent Cabinet reshuffle Barnaby Joyce was sworn in as Deputy Prime Minister and Minister for Infrastructure and Transport.

In 2021, Barnaby was elected by his party colleagues as the Leader of the Nationals and subsequently sworn in as Deputy Prime Minister and Minister for Infrastructure, Transport and Regional Development. Following the change of Government in 2022, Barnaby took on the role of Shadow Minister for Veterans' Affairs, having served in the Army Reserve following in the footsteps of his Father and Grandfather who all served in the military.

He is a Paul Harris Fellow of Rotary, a former serving member of the Australian Defence Force Reserves and a long-term member of St Vincent De Paul. Barnaby is strongly committed to bringing his passionate advocacy for rural and regional Australians, to the New England Electorate.