Tasmanian Deputy Premier Jeremy Rockliff is the island state's 47th premier, after being elected unopposed by the governing Liberal Party.
Mr Rockliff replaces Peter Gutwein, who on Monday announced his resignation after 20 years in politics and two years in the top job.
He was appointed leader at a Liberal partyroom meeting on Friday morning.
"I am honoured and immensely excited to be elected by my parliamentary colleagues," he said.
"It's a great privilege to have the support of my colleagues and continue the ... work of my predecessors."
Mr Rockliff, who was elected to parliament in the northwest electorate of Braddon in 2002, has been deputy premier since the Liberals came to power in 2014.
He indicated he would retain the health and mental health and wellbeing portfolios.
Mr Rockliff, 52, who is married with three children, grew up on his family's farm in Sassafras.
"I love Tasmania. I love our people. I was born here, I was bred here, I've farmed here," he said.
"I will do everything I possibly can to ensure Tasmania seizes every opportunity possible.Tasmania is in my blood."
Infrastructure and Transport Minister Michael Ferguson will be the state's new deputy premier. He was the only MP to nominate for the role.
He will also take on the role of state treasurer, which had been held by Mr Gutwein since 2014.
Mr Ferguson was expected to face off in a two-way battle with Attorney-General Elise Archer for the deputy position, but Ms Archer pulled out of the race.
Mr Gutwein cited a draining pandemic workload and a desire to spend more time with family as reasons for pulling the pin.
Mr Rockliff said he would have more to say next week on the make up of his cabinet.
