Kate Carnell said the selection of Ms Lee, a female who hails from the party's moderate faction, represented a fresh start for a party which has lost the past six ACT elections.

The Liberals will also have the first all-female leadership pairing in the history of the ACT Legislative Assembly, with Giulia Jones chosen to serve as Ms Lee's deputy.

"I think it is a great step in the right direction," Ms Carnell, who was chief minister from 1995 to 2000, said.

"One of the things about this is ... what is the definition of insanity? Doing the same thing over and over and expecting a different result.

"If you want a different result, you do things differently. I think this is a good team to take on the Labor-Greens government."

Former Liberal chief minister and senator Gary Humphries said Ms Lee's leadership was a chance to reset the party's prospects for the 2024 election.

"It will show people there is new life and direction in the party," he said.

"Given our long history of putting in middle-aged white men, the idea of someone as different as Elizabeth leading the party creates a whole new dynamic that would be really helpful in recapturing people."

But Mr Humphries said the party needed to do more than just insert a moderate leader.

"We need to change things with substantive policies that align the party with the aspirations and values of Canberra people," he said

"The leader only partly sets the agenda. If voters detect it's an arch conservative parading behind a moderate leader they won't go for it."

Mr Humphries and Ms Carnell were both aligned with the Liberals' moderate wing.

Ms Carnell said Ms Lee should spend the next six to 12 months speaking to as many people as possible, using their feedback to help frame the Liberals' policy positions ahead of the 2024 election.

She was surprised it had taken more than 20 years for the Liberals to select their next female leader, particularly given the high proportion of women in the ACT Legislative Assembly.

"I think it is a good outcome for the Liberal party," she said.