Liberal senator Greg Mirabella has been sworn into the Senate after being rubberstamped by the Victorian parliament in December.
Senator Mirabella entered the chamber alongside Victorian Liberal senators Jane Hume and James Paterson before reciting the oath of allegiance and signing the senator's roll.
Senator Mirabella replaced retired former Senate president Scott Ryan.
The husband of former Liberal MP Sophie Mirabella has positioned himself as a voice for country Victoria, saying the state's agricultural sector is under-represented in parliament.
He narrowly defeated Treasurer Josh Frydenberg's former adviser Simon Frost to be listed third on the coalition's Senate ticket in Victoria for the federal election, expected in May.
Third spot is widely seen as the ticket's final winnable spot.
